INTEGRATED SCIENCE
COURSEBOOK FOR YEAR 7
CONTENTS
SECTION ONE: INTRODUCTION TO SCIENCE ...................................................................................................1
UNIT 1: INTRODUCTION TO INTEGRATED SCIENCE ....................................................................................1
END OF UNIT QUESTIONS......................................................................................................................22
UNIT 2: MEASUREMENT............................................................................................................................24
END OF UNIT QUESTIONS......................................................................................................................47
SECTION TWO: DIVERSITY OF MATTER .........................................................................................................49
UNIT 1: MATTER ........................................................................................................................................49
END OF UNIT QUESTIONS......................................................................................................................64
UNIT 2: THE NATURE OF SOIL ...................................................................................................................66
END OF UNIT QUESTIONS......................................................................................................................78
UNIT 3: HAZARD .......................................................................................................................................79
END OF UNIT QUESTIONS......................................................................................................................87
SECTION 3: CYCLES ........................................................................................................................................88
UNIT 1: LIFE CYCLE OF FLOWERING PLANT ..............................................................................................88
END OF UNIT QUESTIONS .......................................................................................................................104
UNIT 2: VEGETABLE CROP PRODUCTION ...............................................................................................105
SECTION 4: SYSTEMS...................................................................................................................................122
UNIT 1: FARMING SYSTEMS ....................................................................................................................122
END OF UNIT QUESTIONS....................................................................................................................130
UNIT 2: RESPIRATORY SYSTEM OF HUMANS ..........................................................................................132
END OF UNIT QUESTIONS....................................................................................................................140
SECTION 5: ENERGY ....................................................................................................................................142
UNIT 1: SOURCES OF ENERGY .................................................................................................................142
UNIT 2: CONVERSION AND CONSERVATION OF ENERGY .......................................................................151
UNIT 3: LIGHT ENERGY ............................................................................................................................160
END OF UNIT QUESTIONS....................................................................................................................181
UNIT 4: BASIC ELECTRONICS ..................................................................................................................183
END OF UNIT QUESTIONS....................................................................................................................197
SECTION 6: INTERACTIONS OF MATTER .....................................................................................................199
UNIT 1: ECOSYSTEM ................................................................................................................................199
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UNIT 2: AIR POLLUTION ..............................................................................................................................7
UNIT 3: PHYSICAL AND CHEMICAL CHANGE .............................................................................................14
Commented [bm1]:
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SECTION ONE: INTRODUCTION TO SCIENCE
General objectives
✓ develop awareness of the relationship between various scientific fields
and their interconnectedness.
✓ develop scientific approach to problem solving.
✓ be aware of the influence of Science and Technology on the
development of society.
✓ recognize the need for humans to quantify their interaction with the
environment.
✓ show an appreciation of scientific attitudes such as precision, and
accuracy in making measurement.
✓ recognize the need for humans to quantify their interactions with the
environment through estimation and accurate measurement of
physical quantities.
UNIT 1: INTRODUCTION TO INTEGRATED SCIENCE
LESSON 1: By the end of the lesson student will be able to;
o Explain what is meant by the term science
o Outline the subjects that make up natural science and applied
science.
o Explain the term integrated science.
1.1 WHAT IS MEANT BY THE TERM SCIENCE?
Science has become an essential part of our everyday living. Think about the
things and equipment we use in our everyday lives from simple to
sophisticated ones. For example, we brush our teeth with toothpaste every
morning. This is because the toothpaste kills germs in our mouth to give us
good breath. Science has explained why we need to brush our teeth.
Science comes from the Latin word scientia which means knowledge.
Though there are many definitions to explain science,
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Science can be defined as a method of obtaining knowledge through
observation and experimentation to explain natural phenomena.
Science is the concerted human effort to understand the natural world and
how the natural world works.
1.2 NATURAL SCIENCE AND APPLIED SCIENCE
Science is a broad field. It has many branches and has been classified into
two major branches namely; natural and applied science.
NATURAL SCIENCE
Natural science deals with the study of the natural or physical world and its
events that take place. When studying natural science, scientists describe,
explain and predict without worrying about the practical aspect.
There are three main branches of natural science: biology, physics and
chemistry.
✓ Physics: The study of matter and energy and the interactions between
them. Physicists study such subjects as gravity, light, time mechanics,
motion, waves, electricity, nuclear reactions and force. They use
scientific theories to build materials we use in our everyday life.
✓ Biology: it is the science of life or living organisms (plants and animals).
Biologists study the structure, function, growth, origin, evolution and
distribution of living organisms. There are numerous branches of
biology; anatomy, genetics, microbiology, physiology, ecology,
parasitology, cytology, etc.
✓ Chemistry: it is the study of chemical reactions and properties of
matter. It deals with the composition, properties, reactions, and the
structure of matter. A person who studies chemistry is called chemist.
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OTHER BRANCHES OF NATURAL SCIENCE INCLUDE;
✓ Geology is the science that deals with the earth’s physical structure
and substances, its history and the processes that act on it.
✓ Astronomy is the branch of science that deals with celestial objects,
space, and the physical universe as a whole.
✓ Meteorology is the branch of science concerned with processes and
phenomena of the atmosphere, especially as a means of forecasting
the weather.
APPLIED SCIENCE
Applied science deals with the practical use of the scientific knowledge
acquired in natural science. Applied science is the blueprint of
technology. Some fields of applied science are engineering, medicine,
pharmacy, agriculture, electronics and material science.
✓ Engineering is the branch of
science and technology that is
concerned with the design,
building and use of engines,
machines and structures.
Figure 1.1 engineers at work
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✓ Medicine is the science
and art that deals with the
maintenance of health and
the prevention, alleviation, or
cure of disease.
Figure 1.2 doctors at work
✓
Pharmacy is the
science or practice of the
preparation and
dispensing of medicinal
drugs and safe use of
pharmaceutical drugs.
Figure 1.3 a pharmacist at work
Agriculture is the branch of
science that deals with the
cultivation of crops and the
rearing of animals. It is the
production of food, fibres
and product from plant
and animals.
Figure 1.4 a farmer at work
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✓ Electronics is the science and technology concerned with the
development, behaviour and applications of electronic devices
and circuits.
✓ Information and communication technology (I.C.T) is concerned
with the storage, retrieval, manipulation, transmission or receipts of
digital data.
✓ Material Science is the study of the characteristics and uses of the
various materials, such as metals, ceramics and plastics which are
employed in science and technology.
Questions
1. In your own words define science.
2. Discuss the differences between natural and applied science.
3. Read the following statement and indicate whether it is natural or
applied science.
a) Why is the fan not working?
b) How do I remove the stains from my uniform?
c) What is anatomy?
d) Why do I sweat when I run?
e) Why is the earth far from the sun?
f) How do I make this dirty water clean?
g) How old is the earth?
Activity 1.1
a) Identify some natural phenomena in the environment or society and
explain how scientific knowledge has help to explain those events.
b) Imagine you want to be a pharmacist. Find out which science subjects
you would study in order to prepare and dispense medicinal drugs.
c) Why do you want to become a pharmacist?
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1.3 MEANING OF INTEGRATED SCIENCE
Integrated science involves teaching and learning several fields of science in
a holistic manner. This is done in such a way that none of the fields stands out
on its own. The various fields of science cannot be separated from each
other because they are related. In other cases, some aspect of other
sciences may be involved.
For example, in studying agriculture, one needs to have knowledge in
biology and chemistry and physics. In the study of agriculture, you need to
know insects and pest management (biology), soil chemistry and application
of fertilizers (chemistry) and farm power and machinery (physics).
SUMMARY
➢ Science can be defined as a method of obtaining knowledge
through observation and experimentation to explain natural
phenomena.
➢ Science is classified into two namely; natural science and applied
science.
➢ Natural science deals with the study of the natural or physical world
and its events that take place.
➢ The three main branches of natural science are; biology, physics
and chemistry.
➢ Applied science deals with the practical use of the scientific
knowledge acquired in natural science.
➢ Some fields of applied science are engineering, medicine,
pharmacy, agriculture, electronics and material science.
➢ Integrated science involves teaching and learning several fields of
science in a holistic manner.
LESSON 2: By end of the lesson, student will be able;
o Define scientific method
o Outline the systematic approach used in solving scientific problems.
o Give at least four attitudes and skills of a good scientist.
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1.1 HOW SCIENTISTS WORK
There are thousands of problems in the society and scientists work to find
answers or solutions to the problems confronting society using scientific
method. There are various ways individuals gather and find solutions to
questions and problems that we encounter in our everyday life, but that of
scientist must be step by step or systematic.
The systematic process of solving problems by scientists is called scientific
method.
1.2 THE APPROACH OR THE METHOD USED BY SCIENTISTS.
✓ Identification of problem; it involves making an interesting observation,
taking note of something worth for further thought, asking questions to
find solutions to them.
Suppose you left your food overnight and it has gone bad. You have
observed that the food had gone bad (observation), then you begin to
ask questions like, is it because I didn’t heat the food or store it at the right
temperature?
✓
Hypothesis formulation: it involves making guess as to possible
answers to the identified problem. Hypothesis should be based on
evidence or facts. A hypothesis is a potential answer to the question,
one that can somehow be tested. Hypothesis are always subjected to
modification, they can accepted or rejected.
Your hypothesis can be that; the food was poisoned or went bad
because the food was not heated or put in a refrigerator. So, I can
prevent the food from going bad by putting it a fridge or applying heat.
✓ Experiment: it involves an orderly procedure to test the hypotheses.
You carry out experiment to test your hypothesis formulated by putting the
food in the refrigerator or heating the food on a burner. The procedures to
follow are:
i.
title of the experiment.
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Your title can be; how to prevent food spoilage.
ii.
Aim of the experiment-what you would want to achieve at the end
of the experiment.
Your aim can be: To show that heating or refrigeration prevents food
spoilage.
iii.
Apparatus / materials needed to carry out the experiment.
iv.
Method to used-how you would carry out the experiment.
v.
Observation and recording of data-observing and recording what
happened during the period of the experiment.
vi.
Deductions and conclusion- making reasonable and correct
deductions and conclusion based on the data collected.
✓ Analysing data: it involves interpreting the data collected. Graphs can
be used to analyse your data.
✓ Conclusions: making conclusion of the idea that has been proved
correct.
Your conclusion can be that heating food or putting food in the refrigerator
prevent food from spoiling. If more and more evidences support your findings
and hypothesis, they gain widely acceptance and become theories
1.3 ATTITUDE AND SKILLS OF A GOOD SCIENTIST.
In order for you to be a good scientist, you must have certain attitudes and
skills to follow the scientific method.
✓ You must be a good observer.
✓ You must be a good questioner of events.
✓ You must be a critical thinker.
✓ You must know how to collect and record data systematically.
✓ You must be interested in research.
✓ You must be able accept failure and overcome.
✓ You must be able to select good ideas.
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QUESTIONS.
1. Outline the system approach you will use as a scientist to solve an
outbreak of malaria at Dodowa and its environs.
2. Imagine you want to become a scientist, how would you conduct
yourself in order to become a good scientist.
Activity
1.2 how do you make water containing particles safe for drinking?
a) Things/materials needed: pond water containing particles, filter paper
or cotton wool, beakers or suitable containers and funnel.
Procedure to follow:
✓ Work in groups.
✓ From your knowledge in how scientists work, come out with plans and
ideas to carry our simple experiment on filtration.
✓ Find the differences between filtrate and residue.
✓ The below set up will help you.
Questions:
✓ which one is the filtrate?
✓ Which one is the residue?
b) Use the internet to find out how
Alexander Fleming used scientific method to discover penicillin as an
antibiotic.
SUMMARY
➢ Scientists work by a step by step process called scientific method.
➢ The step by step process involves identification of problem, making
hypotheses, carrying experiment, analyses of data and drawing
conclusions.
➢ Hypothesis and finding verified by scientist increasingly become a
theory.
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LESSON 3: By the end of the lesson, student will be able to;
o Make an observation of different leaves using hand lens.
o Give difference among the leaves
o Analyse a given data and make deductions.
1.1 MAKING OBSERVATION
Activity
1.3 how to make an observation of leaves using hand lens.
a) things/materials needed: hand lenses and different kind of leaves from
school compound.
b) work in groups.
c) Collect different kinds of leave from plants in the school compound.
d) Put the leaves on your table.
e) Use the hand lens to observe the leaves and group them into broad,
narrow, smooth and rough leaves.
f) Compare your observations with other groups.
1.2 DEVELOPING ANALYTICAL SKILLS
Scientists analyse results they have recorded from experiment.
They depend solely on the information recorded without twisting the facts to
agree with what they believe in or thinks is right.
Activity
1.4 how to analyse a recorded data
Table 1.1 below show a data collected on the number of four regions in
Ghana in 2009. Study it carefully and answer the questions that follow.
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Table 1.1 Number pupils in basic schools
Region
Greater Accra
Girls
132,814
Boys
124,356
Ashanti
258,621
268,375
Northern
180,753
212,567
Volta
131,272
144,110
a) Find the region/s which had the largest number of pupils.
b) Find the region/s which had the least number of pupils.
c) Find the total number of boys in the four regions.
d) Find the total number of girls in the four regions.
e) In which region/s were there more boys than girls?
f) In which regions/s were there more girls than boys?
g) What is the total number of pupils in the four regions?
h) Use the information to draw a bar chart.
i) What inference/conclusion can you make from the data?
LESSON 4: By the end of the lesson, student will be able;
o Define the term technology.
o Describe the relationship between science and technology.
o Give at least four (4) difference science and technology.
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1.1 TECHNOLOGY
Technology can be defined as the application of scientific knowledge and
skills to make work easier and faster. Scientific knowledge is the knowledge
acquired through science. Technology can be thought as an applied
science.
It also involves the combination of techniques, skills, processes, design and
products for creating instruments or gadgets to make work easier and faster.
Technology is about ‘doing’ i.e. applying the scientific knowledge to solve
problems confronting us.
1.2 HOW SCIENCE AND TECHNOLOGY ARE RELATED
Science and technology cannot be separated from each other.
Scientific knowledge provides a major source of input for technological
outcome i.e. technology uses the knowledge acquired through science to
solve problems.
Technological outcome provides a way for science to gain better view of the
natural world. Example, microscope and telescope helps to us to see things
that cannot be seed with our naked eyes.
This means that both science and technology solve human problems.
QUESTION:
Identify a need in your locality and design and make an artefact to solve the
need.
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1.3 DIFFERENCES BETWEEN SCIENCE AND TECHNOLOGY
SCIENCE
• Science deals with acquisition of
knowledge and explanation of
the natural world
TECHNOLOGY
• It deals with the application
knowledge and skills for various
purposes
•
Science deals with discoveries
•
It deals with inventions
•
Science deals with theories.
•
Technology is all about process.
•
Science is used to make
predictions.
•
It simplifies work and fulfil the
needs of people.
QUESTIONS:
1. In your own words define the term technology.
2. In a table form, give four differences between science and
technology.
3. Briefly explain how science and technology co-exist.
Activity
1.5 Debate on Science and technology
a) Work in groups.
b) Group A represents science and Group B represents technology.
c) Who is more important, science or technology?
SUMMARY
➢ Technology can be defined as the application of scientific knowledge
and skills to make work easier and faster.
➢ Science is ‘knowing’ and technology is ‘doing’
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LESSON 5
By the end of the lesson, student will be able to;
Explain at least four areas of life where science and technology have
brought improvements.
POSITIVE EFFECTS OF SCIENCE AND TECHNOLOGY IN OUR LIVES
The advancement of science and technology have enormous positive
effects in all facets of our lives, from transportation to health to
communication and so on.
✓ TRANSPORTATION: Science and technology have made
transportation easier and faster. Science and technology have
led to comfortable and reliable movement of goods and people
from one place to another. It has helped in advancing all the
four types of transportation and these include;
1. road transport which is used by automobiles
2. air transport which is used by airplanes
3. water transport which used by ships and boats
4. space transportation used to go to the moon.
Figure 1.2 an airplane to aid air transport
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Figure 1.3 automobiles to aid in road transport
Figure 1.4 ship to aid in water transport
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COMMUNICATION:
Science and technology
have improved
communication. Through
science and technology
people can see and hear
events that occur
everywhere in the world.
The use electronic media
like radios, televisions and
internet have improved the
way we exchange ideas
which in turn has brought
great development in the
way information is
conveyed and shared
among us.
EDUCATION:
Science and technology
have improved teaching
and learning process.
Technologies like smart
whiteboard, computers,
mobile phones, iPad,
projectors and internet
are being used in the
classroom to enhance
teaching and learning in
the education sector.
Figure 1.6. modern classroom setting
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Through science and technology people can do their assignment and have
online programme using the internet. It has also enabled educators to share
information to improve their experiences.
AGRICULTURE: Science and technology
has improved agriculture through
mechanized farming. Mechanised farm
equipment such as plough, combine
harvest, seed planter has made farming
easier and convenient. The use of
science and technology in agriculture
has resulted in the manufacturing of
engineered crops which can grow fast
and resistant to pest and diseases, has
improved storage of food, improve the
nutritional value of food etc.
Figure 1.7 mechanised farming
HEALTH: Application of science
and technology have led to the
production of vaccines and
drugs to fight against diseases
such malaria, small pox,
HIV/AIDS, Ebola, measles etc.
Ultrasound machines are used
to check the growth and health
of foetus growing in the womb
and to detect abnormalities.
Technology has enabled
doctors to use emails, videos
and conference facilities to
consult colleagues from all over
the world.
Figure 1.8 using ultrasound scan machine
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Figure 1.9 modern surgical theatre
ENERGY: Through science and technology, more and varied energy source
have been made available to us. Science and technology have made it
possible to generate electricity from moving water, using solar panels or solar
heater to collect and store solar energy for domestic purposes, windmills to
convert energy from the wind into more useful forms, production of biogas
using bio-digester through fermentation of organic matter.
Figure 1.10 Akosombo hydro-project
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Figure 1.11 Ghana 100 mW solar project
QUESTIONS:
State three uses of science and technology in the following areas;
i.
Health
ii.
Education
iii.
Energy
iv.
Agriculture
SUMMARY
➢ Science and technology have brought a great breakthrough in our
society.
➢ In health, it has help produce drugs and vaccine to cure and alleviate
diseases such, malaria, measles etc.
➢ In agriculture, it has brought about mechanised farming.
➢ In education, the use of projector, smart whiteboard etc. have made
teaching and learning convenient.
➢ In communication, it has made it possible to hear and see events
taking place all over the word.
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Activity
1.6 Effects of science and technology
a) Work in groups.
b) Go around your school compound and identify areas where science
and technology are needed.
c) Discuss how these needs would help improve teaching and learning in
your school.
LESSON 6: By the end of the lesson, student will be able to;
o Explain four negative effects of science and technology in our
society.
o Identify for misuse of science and technology in the society.
1.1 NEGATIVE EFFECTS OF SCIENCE AND TECHNOLOGY.
Although, science and technology has brought great improvement in our
lives, it has some negative effects. Some negative effects are;
✓ Increased in Pollution: the advancement of science and technology
has resulted in the manufacturing and processing which release
harmful chemicals and gases into the environment, rapid destruction of
the forest for building and construction purposes and burning of
organic matter has resulted in global warming.
Global warming is the rise in
temperature as a result of
release of greenhouse gases
such excessive carbon (IV)oxide
and carbon monoxide,
Chlorofluorocarbons (CFC) from
refrigerators and air conditioners
etc.
Figure 1.12 industrial pollution
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✓ Resource depletion: The manufacturing of gadgets and equipment
leads to exploitation of natural resources like gold, aluminium,
diamond, crude oil. Continuous exploitation of these resources
unsustainably will affect future generation.
✓ Through the increasing use of computers and robots, a lot of people
have been thrown out of employment because these machines are
more efficient and faster.
✓ Accidents caused through motor vehicles, industrial machines,
commercial plane or train as a result of science and technology take
away numerous lives, destroys properties and affect the development
of society.
QUESTION:
Identify an area in your locality where science and technology have
negatively affected.
1.2 MISUSE OF SCIENCE AND TECHNOLOGY IN OUR SOCIETY
✓ Some people use poisonous chemical for hunting. For example, some
fishermen use DDT for fishing. The chemicals do not only kill the fishes
but kills other microorganisms in the water which destroys the aquatic
habitat.
✓ Humans have used scientific knowledge to produce sophisticated
guns, atomic bomb and nuclear bombs to destroy lives and property.
For example, atomic bomb killed 60,000 and destroyed a lot of
properties during the world war II in 1945.
✓ Cybercrime: Science and technology has led to using computer and
internet for criminal activities such as fraud, theft, distribution of
pornographic materials.
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Computer fraud include hacking into computer system of a company
or another person to retrieve information, sending computer virus for
personal gain or damage.
✓ Excessive use of fertilizers and pesticides pollutes the environment
and increases the salinity of soil. Increased in salinity affects plants
growth and other living organisms in the soil.
QUESTIONS:
1. Explain four negative effects of science and technology in our
society.
2. Explain four ways in which science and technology has been used
wrongly.
3. Explain the term ‘computer fraud’
SUMMARY
Science and technology have some negative effects and uses such as
using chemicals like DDT for fishing, production of atomic and nuclear
bombs for destruction of lives and properties, increased unemployment
and the use of computer for fraud.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. Which of the following area of study is an applied science?
A. Chemistry
C. Agriculture
B. Biology
D. Geology
2. All the following are importance of science and technology except
A. Science and technology have promoted good health
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B. Science and technology have made transportation faster and
easier
C. Science and technology have made communication faster and
easier
D. Science and technology have helped in cybercrime
3. The step by step approach used by scientist to solve everyday
problems is called……
A.
Scientific research
B.
scientific method
C.
Science research
D.
scientific knowledge
4. The combination of techniques, skills, processes, design and products
for creating instruments or gadgets to make work easier and faster is
called ……
A. Science
B. Technology
C. Science and technology
D. Hypothesis
5. All the following are procedures for carrying out experiment except
A. Title of experiment
B. Aim of the experiment
C. Apparatus
D. Hypothesis
6. Which of the following statement about science is not correct
A. science has help in the exploitation of natural resource
B. science has provided all solutions to the world’s problem
C. science has brought about improved health and education
D. science has made communication easier and faster.
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UNIT 2: MEASUREMENT
LESSON 1: By the end of the lesson, student will be able to;
o Define physical quantity.
o Define SI unit.
o State the types of physical quantities.
o State the fundamental/basic quantities
o State the units of the fundamental quantities
o Identify the instrument used to measure physical quantities.
1.1 PHYSICAL QUANTITIES
Measurement is a significant and inseparable part of our daily life and for the
study of science. The doctor, shopkeeper, seamstress, carpenter etc make
use of measurement in their field of work. In making technological artefacts
measurement in done. Which means that measurement helps scientists to
solve problem facing society.
✓ Physical quantity is anything that can be measured. For example,
measuring the length of your table, the mass of your exercise book,
area of your classroom and measuring the time taken by a runner to
complete 100metre race.
✓ In order for measurement to be generally understood and accepted,
the scientific community adopted standard units of measurement
called Système International d'Unités (SI Units).
✓ SI unit comes from the French name Système International d'Unités. It
is the most commonly used metric system.
✓ Standard unit is a unit of measurement that is understood and
approved by scientists all over the world.
1.2. TYPES OF PHYSICAL QUANTITIES
There two main types of physical quantities of measurement namely;
✓ Fundamental or base quantities.
✓ Derived quantities.
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1.3 FUNDAMENTAL QUANTITIES
✓ Fundamental quantities are the simplest physical quantities that are
independent of other physical quantities and from which other
quantities are formed. There are seven fundamental quantities that
have been identified.
The three main fundamental quantities are length, mass and time.
 Mass is the quantity of matter in an object.
 Length is a distance between two point.
 Time is a measure of interval or period between events.
The units of fundamental quantities are called fundamental units
SI base units are units that cannot be expressed in terms of two or
more base units.
Below is the summary of the seven base quantities.
Table 1.1 fundamental quantities and their units
BASE/FUNDAME
SI UNIT
SYMBOL OF UNIT
Mass (m)
kilogram
Kg
Length (l)
metre
M
Time (t)
Seconds
S
Temperature
Kelvin
K
Ampere
A
mole
Mol
candela
Cd
NTAL
QUANTITIES
&SYMBOLS
(T)
Electric current
(I)
Amount of
substance (n)
Luminous
intensity (lv)
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1.4 INSTRUMENTS USED TO MEASURE PHYSICAL QUANTITIES.
✓ Mass: The following instruments are used to measure the mass of an
object;
•
Beam balance
•
Electronic balance
•
Top pan balance
•
Lever arm balance
Beam balance
Electronic balance
✓ Length: The following instruments are used to measure the distance
between two point;
metre rule.
micrometer screw
gauge
Vernier caliper
Tape measure
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✓ Time: The following instruments are used to measure interval between
two events;
Stop watch
stop clock
✓ Temperature: The instrument used to measure the degree of hotness
of a body is called thermometer. It can be digital or analogue.
Digital thermometer
infrared thermometer
analogue thermometer
✓ Luminous intensity: Photometer used to measure the intensity of light
in a given place.
Photometer
ammeter
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✓ Electric current: Ammeter is used to measure electric current.
✓ Amount of substance: it is measured by mole counter.
SUMMARY.
➢ Physical quantity is anything that can be measured.
➢ Standard unit is a unit of measurement that is understood and
approved by scientists all over the world.
➢ The simplest physical quantity is called fundamental quantity.
➢ SI unit a standard unit of measurement.
QUESTIONS:
1. Copy and complete the table below.
Function-used for
Instrument
measuring
1. Volume of liquids
2. Temperature of a malaria
patient
3. Mass of an exercise book
4. Electric current
5. Length of school walkway
6. Internal diameter of a tube
7. Time
2. Write the SI units of the following physical quantities.
I. length …………………………………
ii. mass……………………………………
iii. temperature……………………………...
iv. time……………………………………...
v. amount of substance ………………………
vi. electric current ……………………………
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LESSON 2: By the end of the lesson student will be able to;
o measure the mass of an object correctly.
o Measure a length correctly.
o Measure temperature correctly.
1.1 HOW TO MEASURE A MASS.
The mass of an object depends on the material from which is made. We use
balances to measure mass of an object.
Mass is the quantity of matter in a substance.
The unit of mass in kilogram (kg).
If we are measuring small objects, we can use grams (g).
If we are measuring very smaller object, we can use milligrams(mg) and if we
are measuring very small object, we can use microgram (µg)
The mass of an object is not the same as its weight. Weight of an object is a
measure of gravity on that object. The mass of an object is constant
irrespective of its position on the earth’s surface or planet but the weight of
an object varies on the earth’s surface and from planet to planet. For
example, if the mass of your pencil on earth is 1kg, its weight is 9.8N. this is due
to the gravitational pull exerted on the pencil.
The unit of mass is kilogram (kg) but the unit of weight is Newton (N)
Activity
how to measure the mass of an object
a) things needed; electronic balance, kitchen scale, exercise book,
pencil and pen.
b) Teacher will guide you how to use the electronic balance.
c) Use the electronic balance to measure the mass of the pen, pencil
and exercise and record your readings in grams (g)
d) Use the kitchen scale to measure the pen, pencil and exercise book
and record your readings.
e) Compare your answers on the different scales.
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QUESTION: In a table form, illustrate the differences between mass and
weight.
1.2 HOW TO MEASURE LENGTH.
Length is measured in metres (m). If we want to measure a very long
distance, we use kilometres.
In taking measurement of
length, it must be measured
at angle 900 to avoid wrong
measurement.
in figure 1.1 the correct
measurement is 4.8cm
figure 1.1 measuring length
If we are measuring small things, we use centimetres, if we are measuring
smaller things, we use millimetres and if you are measuring smallest thing,
we use micrometre. Vernier calipers and micrometer screw gauge are
used to measure small length.
Activity
1.2 how to measure a length.
a) In this activity you are going to use a metre rule.
b) Things needed: exercise book and a metre rule
c) Place the 0 mark on the ruler exactly at one end of your exercise
book.
d) Read the scale at the other end of the exercise book.
e) Avoid parallax when reading i.e. read the mark on the ruler at right
angle (900 to the mark).
f) Record your answer.
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1.3 HOW TO MEASURE TEMPERATURE.
Temperature refers to the degree of hotness of a body. It is measured by a
thermometer. Thermometer can be digital or analogue.
Digital thermometer
analogue thermometer
It is measured in Kelvin (K). temperature can also be measured in degree
Celsius (0C). The normal body temperature of a healthy person is 370C.
Activity
1.3 measuring temperature.
a) Things needed: thermometer, clamp and hot water.
b) Put the thermometer in hot as shown in the diagram below.
c) Measure the temperature of the hot every five minutes for 30
minutes as the it cools.
d) Record your reading in the table 1.3
e) Let’s your teacher guide you to use your data to draw a graph.
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Table 1.3 table showing recording of temperature
Time/minutes
0
5
10
15
20
25
30
Temperature/0C
SUMMARY
➢ Mass is the quantity of matter is a substance.
➢ Mass of an object is not the same as weight.
➢ Temperature is degree of hotness of a body. The normal human
temperature is 370C.
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LESSON 3: By the end of the lesson, student will be able to;
o Write prefixes of large and small figures.
o Convert unit of mass and length from one unit to another.
1.1 PREFIXES IN MEASUREMENT
In metric system of measurement, units’ prefixes make very large and very
small numbers easier to manipulate and understand. They are multiples of 10
and have their prefix according to the multiple. Table 1.4 show this.
Table 1.4 prefix multipliers and their symbols
Prefix
Symbol
Multiple
Kilo
k
103
Mega
M
106
Giga
G
109
Tera
T
1012
Centi
c
10-2
Milli
M
10-3
Micro
µ
10-6
Nano
n
10-9
Pico
p
10-12
1.2 CONVERSION OF UNITS OF MASS AND LENGTH
NB*
1cm = 10mm
1m= 100cm=1000mm
1km=1000m=100000cm
1g=1000mg
1kg=1000g=100000mg
1tonne=1000kg
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Worked examples
1. Converts the following into metre (m)
a. 200m
b. 1850mm
Answers
a. 100cm = 1m
200cm =
b.
200𝑐𝑚
100𝑐𝑚
×1m = 2m
1000mm = 1 m
1850𝑚𝑚
1850 mm = 1000𝑚𝑚 ×1m
= 1.85m
2. convert 500g to kg
Answer
1000g = 1 kg
500g =
500𝑔
1000𝑔
×1kg
=0.5kg
Activity
1.4 conversion of units of mass and length.
a) Work in groups
b) Things needed: exercise book, metre rule and an electronic balance.
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c) Measure the length and mass of your exercise book in centimetres and
grams respectively.
d) Convert the measured mass to kg and mg.
e) Covert the measured length to m, mm and km.
QUESTIONS:
a) Convert the following into grams (g)
▪
100kg
▪
450kg
▪
1050mg
▪
200mg
b) Convert the following into mm
▪
100cm
▪
20m
▪
200m
▪
1000cm
LESSON 4: By the end of the lesson, student will be able to;
o Define derived quantity
o Give at least five examples of derived quantities
o Obtain the SI units of some derived quantities.
o Know volume of substances.
1.1 DERIVED QUANTITIES
Derived quantities are quantities obtained by combination of two or
more base or fundamental quantities. Derived quantities include: area,
volume, speed, acceleration, density, force, work, pressure etc.
1.2 HOW TO OBTAIN UNITS FOR DERIVED QUANTITIES.
Area = length (m) × breath (m)
m×m
=m2
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Volume = length (m) ×breath(m) ×height(m)
m ×m × m
=m3
Density =
velocity =
𝑚𝑎𝑠𝑠 = 𝑘𝑔 =kg/m3 or kgm-3
𝑣𝑜𝑙𝑢𝑚𝑒 𝑚3
= m/s or ms-1
Acceleration =
𝑣𝑒𝑙𝑜𝑐𝑖𝑡𝑦
𝑡𝑖𝑚𝑒
=
𝑚𝑠−1
𝑠
= m/s2 or ms-2
Force = mass (kg)× acceleration (m) = kg × ms-2 = kgms-2 or N (Newton)
Work = force(N) × distance(m) = Nm = J (joule)
QUESTIONS.
a) Find the area of your exercise book with length 10cm and width 6cm.
b) Find the volume your exercise book with length 10cm, width 6 cm and
height 4cm.
c) Find the density of a stone with mass 4kg and volume 20cm3.
1.3 VOLUME OF LIQUIDS.
Volume of a substance can be defined as the amount of space occupied
by matter.
Volumes of liquids are measured using instrument such as measuring cylinder,
volumetric flask, graduated beaker, pipette, syringe and burette.
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Beaker
measuring
burette
pipette
Cylinder
The SI unit of volume is cubic metre (m3).
Note that litres(l) and millilitres (ml) are commonly used
units for measuring volumes of liquids.
1l=1000ml.
1l=1000cm3
1m3=1000l
Volumetric flask
SUMMARY
Derived quantity
SI unit
Symbol
Area
square metre
m2
Volume
cubic metre
m3
Density
kilogram per cubic
kg/m3
metre
Force
newton
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37
Power
watt
W
Weight
newton
N
Pressure
pascal
Pa or N/
Acceleration
metre per second
M
square
Electric resistance
ohms
Ω
LESSON 5: By the end of the lesson, student will be able to;
o Know how to measure volumes of liquids.
o Calculate for the volume of regular objects.
o Measure volumes of irregular object.
o Give at least four reasons why we should measure accurately.
1.1 HOW TO MEASURE VOLUMES OF LIQUIDS.
✓ To measure the volume of liquids, the liquid is poured into a
graduated container and read at the meniscus.
✓ Meniscus is the curved surface of liquids in a tube. The meniscus of a
liquid may bulge downwards as in water and upwards as in
mercury.
✓ This means that you must read it at eye level-horizontal plane at 900
at meniscus. This is illustrated in figure 1.1.
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Activity
1.5 how to read volume of liquids.
a)
Things needed; measuring
cylinder and water.
b)
Put the measuring cylinder on a
flat surface.
c)
Pour the water into the measuring
cylinder.
d)
Read the volume of the water in
the measuring cylinder at an eye
level.
e) Record your reading in cm3.
1.2 VOLUMES OF REGULAR OBJECTS.
✓ Volume of a cuboid = length × breadth × height
✓ volume of a cylinder
where h= height of the cylinder
✓ Volume of a cone
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where r=radius and h= height
✓ Volume of Sphere
1.3 HOW TO MEASURE THE VOLUME OF IRREGULAR OBJECTS.
The volume of irregular of objects like stone cannot be found as regular
objects because they don’t have regular sides (dimensions), therefore it is
difficult to measure their length, breadth and height.
The only way is to immerse in water and the displaced water is equal to the
volume of that irregular object. This method was discovered by a Greek
philosopher Archimedes.
Activity
1.6 how to measure the volume of an irregular objects
a) Work in groups
b) Things needed: a piece of stone, thread and graduated measuring
cylinder.
c) Pour the water into the measuring cylinder to a suitable level.
d) Read and record the volume, V1
e) Tie the thread to the stone and lower it gently into the measuring
cylinder until it is fully submerged.
f) What happened to the volume of the water?
g) read and record the new volume as V2
h) discuss how to get the volume to the stone.
j) What are the precautions to be taken?
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QUESTIONS
a) The initial volume of water in a graduated beaker is 20cm 3. When a
piece of stone was dropped in the water level of the water rose to
35cm3. What is the volume of the stone?
𝟐𝟐
b) Find the volume of a cylinder of radius 7cm. [take π =
𝟕
].
c) Calculate the volume of a wooden block with length 5cm, breadth
2cm and height 3cm.
1.4 WHY DO WE HAVE TO MEASURE ACCURATELY?
✓ To prevent wastage
✓ To prevent cheating
✓ To avoid drawing wrong conclusion when experiment is conducted
✓ The prevent overdose and under dose in the preparation and
dispensing of medicine
✓ To prevent accident in the transportation system on the sea, air and
land
✓ To prevent pollution when applying chemicals.
SUMMARY
➢ The volume of irregular object is determined by immersing it in water
and the displaced water is the volume of the object.
➢ We must measure correctly to prevent wastage, cheating and to
prevent overdose and underdose of chemicals.
LESSON 6: by the end of the lesson, student will be able to;
o Define density
o Find the density of regular objects
o Find the density of irregular objects.
1.1 DENSITY
✓ Everything in the universe consist of atoms, molecules and ions. How
closely the molecules are packed is the density of that object. Density
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is the measure of compactness of and object. It is expressed in terms of
mass and volume.
✓ Therefore, density can be defined as mass per unit volume of the
substance or body.
✓ Mathematically, density(ρ) =
𝑚𝑎𝑠𝑠
𝑣𝑜𝑙𝑢𝑚𝑒
✓ The standard unit of density is kg/ m3
1.2 DENSTIY OF REGULAR OBJECTS.
To find the volume of a regular object, find the mass and volume of
that object. Divide the mass by the volume to obtain the density of that
object.
Activity
1.7. finding density of regular object
a) Work in groups.
b) Things needed: rectangular block, electronic balance and tape
measure.
c) Use the electronic balance to measure the mass of the block.
d) Measure the length, breadth and height of the block to obtain
the volume.
e) Divide the mass of the block by volume to obtain the density of
the block.
QUESTIONS.
a) What is density.
b) A rectangular block has dimension 10cm × 5cm ×3cm. If its mass
is 30g. calculate the density of rectangular block.
c) If the density of a rectangular block is 4kg/m3 and it has a
volume of 1000m3. Find the mass of the block.
d) The density of a cuboid is 2kg/m3 and has a mass of 10kg. find its
volume.
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1.2. DENSITY OF IRREGULAR OBJECT.
To find the density of irregular objects like stone, we used displacement
method to find the volume of the irregular object as discussed in our previous
lesson 5, 1.12. then use an electronic balance or beam balance to find the
mass of the object and calculate the density.
Activity
1.8 finding the density of irregular object.
a) Work in groups
b) Materials needed: a piece of stone, measuring cylinder, electronic or
beam balance, thread.
c) Measure the mass of the piece of stone using the electronic or beam
balance.
d) Record the mass in grams.
e) Fill your measuring cylinder with water to a suitable volume.
f) Read and record the volume (V1).
g) Tie the thread to the stone and lower it gently into the measuring
cylinder containing the water.
h) Observe the change in the water level
i) Read and record the volume (V2)
j) Find the volume of the stone by subtracting V1 from V2 (V2-V1)
QUESTIONS.
a) A piece of stone of mass 50g was dropped in a measuring cylinder
containing water. The level of water increased from 40cm3 mark to
60cm3. Find the density of the stone.
b) To determine the density of a piece of wood, a cuboid of it was used.
The mass and volume of the cuboid were then determined. Figure 1
shows the dimensions L, W and D of the cuboid while Figure 2 shows the
cuboid on a weighing scale.
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Figure 1
Figure 2
I.
II.
III.
IV.
Measure and record the length L, W and D in centimetres.
Calculate the volume of the cuboid.
Read and record the mass, m of the cuboid.
Calculate the density of the piece of wood in gcm -3.
SUMMARY
➢ Density can be defined as the mass per unit volume of the substance.
➢ The standard unit of density is kg/ kg
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LESSON 6. By the end of the lesson, student will be able to;
o explain why some objects float in water and others sink.
o Give at least three applications of density.
1.1 SINKING AND FLOATING OBJECTS
Activity
1.9 sinking and floating objects.
a. Work in groups
b. Materials needed: 20 paper clips, aluminium foil, a ruler and a
bucket of water.
c. Cut two 30cm squares from the aluminium foil
d. Wrap one of the metal squares around 10 paper clips and squeeze
the foil into a tight ball.
e. Fold the four edges of the second
aluminium foil square up to make a small
square pan.
f. Place 10 paper clips in the metal pan
g. Set the metal pan on the water’s surface
in the bucket
h. Place the metal ball on the water’s
surface
i.
Observe what happens.
j.
The metal pan floats and the ball sinks, WHY?
The explanation of why some objects sink and float is based on the concept
of density.
When the density of an object is more than the density of water, the object
will sink in water but if the density of object is less than the density of water,
the object floats on water.
The density of water is 1g/cm3 or 1000g/m3.
Therefore, any object less 1g/cm3 or 1000g/m3 will float and any object
greater than 1g/cm3 or 1000g/m3 will sink.
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Example: Ships are made of metals
like steel and copper. These metals
are denser than water and will not
float. Ships are hollow objects and it
consist of air and it makes the ships
have larger volume relative to the
mass. This makes the average
densities of ships less than density of
water. Hence ships float.
Figure 1.2 ship floating on water
QUESTIONS.
1.Four liquids Q, R, S and T have the following densities
Q =1.0 g/cm3
R=1.4 g/cm3
S= 1.03 g/cm3
T = 0.93 g/cm3
a. Which of the four liquids will an object of density 1.003g/cm3 float?
b. Draw a sketch to show the various layers into in which the liquids will
settles when mixed together.
2. Give three ways you can make objects to float on water.
3. Give three ways you can make objects to sink in water.
1.2 APPLICATION OF DENSITY
✓ The concept of density is used in construction of ships, boats,
submarines and aircraft.
✓ The knowledge of density helps in the discovery of new element
✓ it is used to determine the purity of a metal
✓ it helps to know the compactness of a substance
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SUMMARY.
When the density of an object is more than the density of water, the object
will sink in water but if the density of object is less than the density of water,
the object floats on water.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1.Which of the following is a derived unit?
A.
Metre
C.
Second
B. Kilogram
D. Cube metre
2. All the following are fundamental quantities except
A. Mass
B. Time
C. Length
D. Force
3. Which of the following is a base unit?
A. Kg
B. mm
C. m3
D. kg/m3
4. Kilogram is the unit for measuring
A. Length
B.
mass
C. Weight
D.
volume
5. What is the SI unit of acceleration?
A. ms-1
B. ms-2
C. ms-3
D. kgms-2
6. Which of the following is the unit of force?
A. Newton per metre
B. Newton
C. Kilogram per second
D. Pascal
7. Which of the following instrument is used to measure the thickness of a
paper?
A. Micrometre screw gauge
B. vernier caliper
C. Metre rule
D. measuring cylinder
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8. Which of the following is true about weight.
A. it is a vector quantity
B. it is a scaler quantity
C. it is measured by beam balance D. it is measured by a ruler
9. Mass is defined as the………………...
A. the amount of space occupied by a matter
B. weight of an object
C. the quantity of matter in an object
D. the movement of an object
10. All the following can be used to measure length except
A. metre rule
B. micrometer screw gauge
C. thermometer
D. venier callipers
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SECTION TWO: DIVERSITY OF MATTER
General Objectives:
✓ recognise the variety of living and non-living things in nature and their
connectedness.
✓ develop scientific approach to problem solving.
✓ understand the nature of matter in its various forms.
✓ be aware of the physical properties of soil in relation to its uses.
✓ be aware of hazards in the communities and the teaching/learning of
science.
UNIT 1: MATTER
LESSON 1: By the end of the lesson, students will be able;
o Explain the term matter
o Describe the nature of matter
o State the three types of matter.
1.1. MEANING OF MATTER
Everything that surrounds us is matter. Matter can be defined as
anything that has mass and occupies space (it has volume). Mass is
the quantity of matter in a substance. Volume is the space something
occupies.
Some examples of matter are; stone, books, table, pen, pencil. Chair,
eraser, whiteboard, ice cream, water etc.
1.2 NATURE MATTER
Matter is made of three basic particles. These particles are:
✓ Atoms
✓ Molecules
✓ Ions.
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Atom is the smallest particle of an element that can take part in
chemical reaction. An element is a substance that is made of the
same kind of atom and cannot be broken down into simpler substance
by any known chemical means. For example, aluminium is an element,
meaning it has one type of aluminium atom.
A molecule is a group of atoms of the same or different elements
chemically combined and exist by itself.
Examples: Oxygen molecule (O2), carbon dioxide (CO2), water (H2O)
Ions can simply be defined as charged particles of atoms. An ion is
formed when an atom loses or gains one or more electrons.
Examples calcium ion (Ca2+), sodium ion (Na+), potassium ion(K+),
chlorine ion (Cl-) etc.
1.3 STATES OF MATTER
Although matter is seen everywhere in the universe, it can be identified
in forms or states on earth.
There are three main states of matter. These
are;
✓
Solids
✓
Liquids
✓
Gases
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There are other states of matter like plasma and Bose-Einstein
Condensate,
but in our environment, scientists have always known solid, liquid and gas.
Solids are substances which have fixed volume and shape.
Liquids are substances which have fixed volume but take shape in containers
Gases are substances which have neither fixed volume nor shape
Activity
1.1 states of matter.
a) Work in groups
b) Group the following substances into the three state of matter.
c) Stone, pen, water, kerosene, brass, oxygen, methane, granite, carbon
dioxide, cement, mercury, bromine, silver, copper, nitrogen, paper,
cooking oil, table, blood, watch, palm wine.
QUESTIONS
1. Define the following terms
a. Matter
b. Atom
c. Molecule
d. Ions
2. State the three states of matter and give five examples each.
SUMMARY
➢ Matter is anything that has mass and volume.
➢ There are three particles that make up matter namely; atom, molecule
and ion.
➢ There are three state of matter namely; solid, liquid and gas.
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➢ Atom is the smallest particle of an element that can take part in
chemical reaction.
➢ Molecule is a group of atoms of the same or different elements
chemically combined and exist by itself.
➢ Ions can simply be defined as charged particles of atoms.
LESSON 2: By the end of the lesson, student will be able;
o State at least five characteristics of solid.
o State at least five characteristics of liquid.
o State at least five characteristics of gas
1.1 CHARACTERISTICS OF SOLIDS
✓ They have fixed shape and volume.
✓ Molecules are tightly packed together.
✓ They do not flow.
✓ They cannot be easily compressed.
✓ Particle of solids have low kinetic energy.
✓ Have strong intermolecular force i.e. the force between the molecules.
✓ Have low rate of diffusion.
✓ Have higher density as compared to liquids and gases
✓ They may crystalline or amorphous
1.2 CHARACTERISTICS OF LIQUIDS.
✓ Have definite volume.
✓ They do not have fixed shape but take shape in containers
✓ Liquids exhibit viscosity.
✓ Have moderately strong intermolecular force.
✓ Particles have high kinetic energy.
✓ Liquid are not easily compressed
✓ Have high density.
✓ They exhibit capillary action.
1.3 CHARACTERISTICS OF GASES
✓ Have indefinite shape and volume
✓ They are easily compressed
✓ Have are easily diffused
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✓ Have weak intermolecular forces.
✓ They have low density
✓ Particles are in random motion.
QUESTION: copy and complete the table below
Characteristics of Solid
particles
Liquid
Gas
Arrangement of
particle
Shape
volume
Fluidity
Compressibility.
Activity
1.2 characteristics of the states of matter.
WORK IN GROUPS
GROUP 1
a) State four differences between solids and liquids.
GROUP 2
b) State four differences between liquids and gas.
GROUP 3
c) Explain why gases have no fixed shape and can be compressed.
GROUP 4
d) Explain why solids have fixed shape and cannot be compressed.
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SUMMARY.
➢ Solids have fixed shape and fixed volume.
➢ Liquids have fixed volume but no fixed shape.
➢ Gases have no fixed shape and no fixed volume.
LESSON 3: By the end of lesson, student will be able to;
o Explain how a state of matter can be change from one state to
another.
o Explain the following; melting, evaporation, condensation and
sublimation.
1.1 CHANGE OF STATES OF MATTER
Matter exists in three states (solid, liquid and gas). Any of the three states
of matter can be changed from one state to another when the
temperature of the material is increased or decreased. This means that a
substance can change its state to another by giving or taking heat. Each
change of state matter has a specific name. The following are the
processes by which a substance can be made to change its state.
✓ Melting
✓ Evaporation
✓ Condensation
✓ Sublimation
✓ Deposition
1.2 MELTING
It is the process whereby a solid change into liquid by heating. For
example, when ice block (solid) is heated gently, it changes to
water(liquid) or when a small piece of candle or shea butter is heated
it changes to liquid.
When ice or butter is heated gently, the molecules gain energy and
overcome the intermolecular force that binds the molecules. This
causes the ice or butter to melt and become liquid.
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The temperature at which both solid and liquid state of a substance
co-exist is called melting point i.e. the specific temperature where solid
changes to liquid. For example, ice becomes liquid at 00C.
Activity
1.3 changing solid liquid.
a) Work in a group
b) Materials needed: Bunsen burner (source heat), shea butter.
c) Heat shea butter gently.
d) Observe what happens.
1.3 EVAPORATION.
✓ it is the process whereby liquid particles on the surface of the liquid
change into vapour below boiling point. In order for a liquid molecule
to escape into the gas state, the molecule must have enough kinetic
energy to overcome the intermolecular attractive forces in the liquid.
✓ As a liquid is heated, the average kinetic energy of its particles
increases. The rate of evaporation increases as more and more
molecules are able to escape the liquid's surface into the vapor phase.
Eventually a point is reached when the molecules all throughout the
liquid have enough kinetic energy to vaporize. At this point the liquid
begins to boil.
✓ The boiling point is the temperature at which the vapor pressure of a
liquid is equal to the external pressure i.e. that the temperature at
which a liquid change to a gas. The boiling of water is 1000C.
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QUESTION.
In a table form, show the differences between boiling and
evaporation.
1.4 CONDENSATION
It is the process by which gas is changed into a liquid by loss of heat
/cooling. For example, conversion of steam into water.
1.5 FREEZING / SOLIDIFICATION
Freezing or solidification is the process by which a liquid change to solid
by cooling. For example, conversion of water into ice. This is
demonstrated by putting water in a freezer to be cooled. During
solidification or freezing, heat energy is given out.
The freezing point of water is zero degree Celsius. The temperature at
which liquid and solid co-exist is called freezing point.
1.6 SUBLIMATION
It is the process by which a substance changes from the solid state
directly to the gaseous state without passing through the liquid state.
Examples of such substances are iodine, ammonium chloride and
naphthalene.
NB Gaseous substances can change directly to the solid state and is
called deposition
QUESTIONS:
a) Describe how a state of matter changes from one state to another.
b) Define the following term.
i.
Melting
ii.
Evaporation
iii.
Sublimation
iv.
Condensation.
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SUMMARY
➢ Matter can change from one state to another when heated is added
and removed from it.
LESSON 4: By the end of the lesson, student will be able to;
o Define living things
o State the characteristics of living things
o Differentiate between living and non-living things
1.1 LIVING THINGS
A living thing is an organism which is capable of performing life processes
or activities or vital function.
These life processes distinguish living things from non-living things.
Living things are made up of plants and animals.
1.2 CHARACTERISTICS OF LIVING THINGS
✓ NUTRITION: Nutrition refers to how living things obtain their food.
Nutrition is needed for growth and energy. Both plants and animals
need food. Plants are able to make their own food through
photosynthesis. Animals depend on plants for food.
✓ RESPIRATION: it is the process whereby living things breathe or respire in
order to obtain energy. It is therefore the oxidation of food to release
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energy. Respiration involves gaseous exchange (external respiration)
and cellular respiration (internal respiration)
✓ EXCRETION: It is the process of removing metabolic waste products
from the body. Metabolic activities lead to the production of poisonous
substance which when allowed could be harmful to the body.
Some of the excretory products include; carbon dioxide, sweat, urine.
✓ MOVEMENT: It is a process that involves the change in position of the
whole or part of the body. You can usually tell if something is alive or
not if it can move by itself without a pull or push. Movement of the
whole body is called locomotion. Living things move to obtain food
and water, find shelter, mates and avoid enemies.
✓ SENSITIVITY/ IRRITABILITY: It is the process by which living things respond
to stimuli or change in both external and internal environments to
ensure survival. Living things can sense what is going on around them,
and are able to respond to them. Living things respond to stimuli such
as sound, heat, pain and chemicals. Plants are able to respond to
stimulus. For example, plants respond to light by growing towards the
light.
✓ GROWTH: It is the increase in size. Living things are usually small when
they start life. They grow and become adult. Some animals grow
through a complete change in their appearance whiles others show
gradual change in appearance.
✓ REPRODUCTION: It is the process by which living things produce new
individuals of their kind (offspring). They reproduce sexually or asexual
means. Animals reproduce in different ways. While some give birth
others lay eggs containing young ones. Most plants reproduce using
seeds and others use part of the parent plant (root, stem, branch or
leaves)
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Activity
1. 4 difference between living and non-living things
a) Work in groups
b) Discuss the difference between living and non-living things.
QUESTIONS:
1. In your own words define living things
2. Write three reasons why living things move from one place to another.
3. List three excretory products you know.
4. List all the life activities performed by living things.
SUMMARY
➢ A living thing is an organism which is capable of performing life
processes.
LESSON 5: By the end of the lesson, student will able:
o Define cell.
o Differentiate between unicellular and multicellular organisms.
o Draw and label plant and animal cell
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1.1 DEFINITION OF CELL
✓ All living things are made of cell. Cell can be defined as the structural
and functional unit of a living thing. Most cells are very small to be seen
with our naked eye. We can only see them with a microscope.
✓ Unicellular organisms are organisms made of a single cell. The cells of
unicellular organisms are not specialised. Examples; amoeba,
paramecium, euglena etc
✓ Multicellular organisms are organisms made of many cells. Examples;
man, rabbits, elephant, monkeys, dogs, etc.
✓ A typical cell has the following parts: cell membrane, cytoplasm,
nucleus, vacuole, mitochondrion, cell wall, and chloroplast.
✓ NB. The nucleus and cytoplasm are collectively known as protoplasm
1.2 PLANT AND ANIMAL CELL.
Plant cell
animal cell.
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Activity
1.5 observing plant cells.
a) Work in groups
b) Things needed: slides, onion, microscope, sharp razor blade, dropper
and cover slip.
c) Cut a small piece of onion about 1cm square.
d) Clean the slide.
e) Use the dropper and put a drop of water on the slide.
f) Carefully peel a thin layer of the piece of onion.
g) Gently put the thin layer of onion into the drop of water on the slide.
h) Your teacher will guide you to lower the cover slip gently on the slide to
avoid bubbles.
i) Mount the slide under the microscope and observe (teacher will guide
you how to focus the lens of the microscope)
j) Make a drawing of some of the cells that you can see
Activity
1.6 observing animal cell
a) Work in groups
b) Materials needed; microscope, methylated blue, blunt toothpick,
cover slip, dropper, slides.
c) Use the toothpick to scrap gently the inside of your cheek.
d) Gently wipe the wet end of the toothpick onto the middle of slide.
e) Add a drop of methylated blue solution and gently place a cover slip
on top of it to avoid bubbles
f) Place the slide under the microscope for observation
g) Draw the cell under the microscope.
LESSON 6: By the end of the lesson, student will be able to;
o
Give the functions of the various parts of a typical cell.
Give at least five difference plant cell and animal cell
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1.1 THE STRUCTURE AND FUNCTIONS OF PLANT AND ANIMAL CELL.
The plant cell is relatively large in size and regular in shape than animal cell,
so it is easier to observe under microscope.
✓ Cell wall: it is found in plant cell. It is made up of cellulose and encloses
the cell membrane.
Functions: it helps to keep the shape of the cell
it gives strength and support to the plant cell
it serves as a protective layer
✓ Cell membrane: it is a flexible layer that encloses the cell. It is made up
of proteins and lipids. It is partially permeable. A partial permeable
membrane is own which allows only certain types of substance to pass
through, depending on their size and nature.
Functions: it controls the movement of substance in and out of the cell.
it protects the internal structures of the cell.
it supports and give shape to the cell
✓ Cytoplasm: it transparent, watery and contains various minute
structures surrounding the nucleus called organelles. Examples are:
vacuole, mitochondrion, ribosome etc.
Functions: chemical reaction takes place in the cytoplasm
it gets rid of waste materials through the cell membrane.
✓ Nucleus: it is large spherical and surrounded by nuclear membrane. It is
composed of watery fluid called nucleoplasm. The nucleoplasm
contains thread –like structures called chromosome, which contains the
hereditary material called genes. The genes are responsible for
inheritance of characters from parents.
Functions: it controls life activities of the cell.
it produces enzyme such as DNA polymerase.
✓ Vacuole: it is a fluid filled sac surrounded by a membrane.
Functions: It stores food such as sugar and amino acids.
it acts as temporary stores for organic waste.
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✓ Mitochondrion: it is a minute rod-shaped body scattered in the
cytoplasm.
Functions: it serves as a site for the release of energy.
✓ Chloroplast: it is a large disc shape organelle containing chlorophyll.
Function: it serves as a site for photosynthesis.
1.2 DIFFERENCES BETWEEN PLANT CELL AND ANIMAL CELL.
Animal cell
Plant cell
Has no cellulose cell wall.
Has cellulose cell wall.
Has no fixed shape.
Has fixed shape.
Has no chloroplast.
Has chloroplast.
Has small and temporary
vacuole.
Relatively smaller in size.
Has large and permanent vacuole.
Relatively larger in size
QUESTIONS:
1.State the functions of the following part of the cell;
a) Cell wall
b) Mitochondrion
c) Nucleus
d) Chloroplast
e) Cytoplasm
2. Explain why the leaf of a plant is green but its root is not
SUMMARY
➢ The cell wall protects and give mechanical support to the plant cell.
➢ The mitochondrion serves as site for energy production
➢ Chloroplast is the site for photosynthesis.
➢ The nucleus controls life activities in the cell.
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END OF UNIT QUESTIONS
OBJECTIVE TEST
1.The green pigment in the chloroplast of a plant cell is called………
A. chlorophyll
B. carotenoid
C. xanthophyll
D. mesophyll
2. Which part of the cell controls al the activities of the cell?
A. chloroplast
B. cell membrane
C. nucleus
D. mitochondrion.
3. Which of the following organelles is not present in animal cell?
A. nucleus
B. cell membrane
C. chloroplast
D. vacuole
4. In which of the following is cellulose found?
A. cell wall
B. cell membrane
C. cell vacuole
D. chloroplast
5. Which of the following organelles is responsible for production of energy for
the cell?
A. cell membrane
B. mitochondrion
C. nucleus
D. vacuole
6. Which organelle contains hereditary materials called gene?
A. mitochondrion
B. nucleus
C. vacuole
D. chloroplast
7. Chlorine gas is an example of …………………...
A. an element
B. a molecule
C. compound
D. an atom
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8. The basic unit of matte is………………...
A. compound
B. atom
C. molecule
D. water
9. How many states of matter do we have?
A. 2
B. 3
C. 4
D. 5
10. Which of the following exist in all the three states of matter?
A. iodine
B. water
C. gasoline
D. milk
11. The process by which water is changed to steam is called………
A. condensation
B. evaporation
C. melting
D. sublimation.
12. A change of state of matter directly from solid to gas is known as……...
A. melting
B. vaporisation
C. sublimation
D. condensation
13. Gas is more compressible than solids because……
A. molecules of solid are closely packed.
B. gas molecules are closely packed
C. the intermolecular force in solids are stronger than gas
D. the molecules of gas are randomly in motion.
14. The chemical combination of the same or different atoms that exist
independently is called……
A. compound
B. molecules
C. mixtures
D. particles
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UNIT 2: THE NATURE OF SOIL
LESSON 1: By the end of the lesson, student will be able to;
o Define soil.
o Describe the components of soil.
1.1 DEFINITION OF SOIL.
Soil is one of the most important natural resource needed by plants for
growth and animals or human beings for various activities. Soil is formed
over a long period of time when its mineral matter breaks down
(through weathering) and organic matter decomposes.
Soil can be defined as the finely divided minerals and organic materials
that covers the earth’s surface that support plant growth.
1.2 COMPOSITION OF SOIL.
The constituents of soil can be grouped into two, namely;
✓ Organic part; humus and living organisms.
✓ Inorganic part; soil particles, mineral salts, water and air.
HUMUS
Humus is mainly made of decomposed plants and animals. It is formed by the
action of bacteria, fungi and other microorganism on dead plants and
animals. Soil rich in humus is dark in colour.
Humus supplies nutrients to plants, improves soil structure, soil aeration,
drainage system of the soil and increase water holding capacity.
LIVING ORGANISMS
Living organisms in the soil include
micro-organisms, plants and animals.
Plants are together referred to as flora
while the animals are referred to as
fauna. Some examples are: bacteria,
fungi, protozoa, earthworm,
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centipede, millipede, ants, termite, roundworm etc.
Living organisms help in aeration, aggregation and drainage of the soil by
the burrow they make. Bacteria and fungi help in the formation of humus by
the decay of plants and animals.
Activity
1.2 determination of soil living organisms.
a) Work in groups
b) Things needed: garden soil and hand lens.
c) Use your hand lens to observe the living organism in the soil.
d) Write your observations.
Questions.
1. In your own words define soil.
2. State the components of soil.
SOIL WATER
Water available to plants is known as soil water. It may exist in the narrow
spaces between soil particles as thin film around each particle.
Water may come from rain, ground water or irrigation. It serves as a medium
in which most nutrients are absorbed and helps in various activities like
photosynthesis and transpiration.
Activity
1.2 determination of soil water
a) Work in groups
b) Thing needed: garden soil, evaporating dish, Bunsen burner and
electronic balance.
c) Put garden in the evaporating dish.
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d) Measure and record the mass of the content.
e) Heat the evaporating dish and its content over a Bunsen for some time.
f) Weigh the content and record the new mass.
g) The difference between the initial and final volume represent the soil
water.
SOIL AIR
Soil air occupies the space between soil particles. It contains mostly oxygen
and nitrogen. It makes oxygen available in plants for respiration.
Activity
1.3 determining soil air
a) Work in a group
b) Thing needed: garden soil, measuring cylinder, water.
c) Put sample of garden soil in the measuring cylinder.
d) Add water to the soil.
e) The bubbles that come out represent the soil air
SOIL PARTICLES
Soil particles are formed from weathering of rocks. Soil is composed of
particles of varying sizes ranging from tiny particles of clay to large particles of
gravel and stones.
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Activity
1.1 showing different soil particle size.
a) Work in groups
b) Things needed: measuring cylinder, garden soil, sodium carbonate and
stirrer.
c) Half fill the measuring cylinder with garden soil.
d) Add water until it is almost full.
e) Add sodium carbonate.
f) Stir until thoroughly until the water mixes with the soil completely.
g) Allow the mixture settle and observe.
h) Make a drawing of all the different particles you see.
MINERAL SALT
Mineral salts are chemical elements in the form of ions which are essential for
plant growth and development. They include elements such as nitrogen,
potassium, calcium, sodium, iron etc
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SUMMARY
➢ Soil is the medium through which plants grow.
➢ Soil has organic component and inorganic component
➢ The organic components include; humus and living organisms.
➢ Inorganic component includes; soil particles, mineral salt, soil air and
soil water.
LESSON 2: By the end of the lesson, student will be able to;
a) Give at least four functions of soil.
b) State the types of soil.
c) Give at least four characteristics of each type of soil
1.1 FUNCTIONS OF SOIL.
✓ It provides nutrients for plant growth and development.
✓ It provides mechanical support for plant by holding their roots firmly in
the ground.
✓ It provides plant with water for transpiration.
✓ It serves a habitat for microorganisms and microorganisms such
earthworms, termites, ants, nematodes, bacteria and fungi.
✓ It is used for construction such as making ceramics, roads, tiles and
pottery.
1.2 TYPES OF SOIL.
There are three types of soil. These are:
✓ Sandy soil
✓ Clayey soil
✓ Loamy soil
NB. Teacher should help students to fetch soil from the garden, road side and
seashore to find the characteristics of the types of soi
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1.3 CHARACTERISTICS OF SANDY SOIL
•
Particles of sandy soil are large in size.
•
The space between the particles
are large.
•
Allows water to pass through
easily.
•
It easily heats up readily during the
day.
•
Mineral salts are easily leached
away by rainfall.
NB. It can be improved by adding humus.
1.4 CHARACTERISTICS OF CLAYEY SOIL.
•
Particles are small in diameter.
•
Sticky when wet and not permeable by water.
•
Aeration and drainage are very poor.
NB. Clayey soil can be improved by adding humus and lime. They break
up the soil and improve its texture. Lime also causes the clay particles to
clump together.
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1.5 CHARACTERISTICS OF LOAMY SOIL
•
Loamy soil has average proportion of
all the components and with good
humus content.
•
It is able to retain water without
becoming waterlogged.
•
It does not become too hard when
dry.
•
It is one of the best soils for farming because it has the good physical
and chemical properties of sandy and clayey soils.
1.5 PHYSICAL PROPERTIES OF SOIL.
✓ The three types of soil differ from each other and each has unique
properties. They differ from each in the following physical properties.
✓ SOIL TEXTURE: It refers to the relative proportion of sand, silt and clay in
a given soil. The texture of the soil determines the water holding
capacity of the soil, soil aeration and penetration of plants roots.
✓ WATER HOLDING CAPACITY: It refers to the ability of soil to retain water.
This depends on the soil texture and organic matter. The water holding
capacity of the soil is determined by the sizes of the pores in the soil. If
the pores are large then the soil will have low water holding capacity
and if the pores are small, the soil will have high water holding
capacity.
✓ Also, the texture and organic matter of the soil affect the water holding
capacity of the soil.
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Activity
1.2 determining water holding capacity of different soils.
a) Work in groups
b) Material needed: three graduated measuring cylinders (equal
sizes and volume), sandy soil, clayey soil, loamy soil, cotton wool,
three funnels, filter paper, stop clock, water and electronic
balance.
c) Line equal amount of cotton wool in the three funnels
d) Place the funnels on the three-measuring cylinder.
e) Put equal amount of soil in the measuring cylinders.
f) Pour equal amount of water into each funnel at the same time.
g) Record the volume of water drained into the measuring for 20
minutes.
h) Discuss your result
✓ SOIL STRUCTURE: it refers to the arrangement of soil particles into
aggregates. Soil can be loosely or tightly packed.
✓ SOIL POROSITY: this refers to the size, number and arrangement of pores
in the soil. It describes how water easily passes through the soil.
✓ SOIL CAPILLARITY: It refers to how water rises up in soil. It determines
the height to which water rises in a soil.
Activity
1.3 determining how water rise in the soil.
a) Work in groups
b) Things needed: three test tube, sample of dry sandy, loamy soil and
clay soil, water trough, capillary tubes, retort stand and clamp, water
cotton wool.
c) Plug one end of each of the capillary tube with cotton wool.
d) Fill the three tubes with equal amount of sandy soil, clay soil and loamy
soil.
e) Fill the water trough with suitable amount of water.
f) Gently place the end of the tubes plugged with cotton.
g) Clamp the tubes to the retort stand.
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h) Leave the set-up for some time and observe the water rise in the
various tube.
i) Note the soil with the highest capillary and lowest capillary.
j) Discuss the differences in the rise of the water.
✓ SOIL TEMPERATURE
The temperature of the soil affects the growth of plants because it
influences how quickly plant take water and nutrients. Activities of
microorganisms slow down if the temperature of the soil is too high and
become inactive when the temperature is too low. When the
temperature is right for a particular plant, its roots will keep growing.
QUESTIONS
1. Give four functions of soil
2. Define the following and describe how each affect plant growth.
i.
Soil texture.
ii.
Soil structure.
iii.
Soil temperature.
iv.
Soil capillarity.
SUMMARY
Characteristics of Sandy
soil
Size of particles
Large
Texture
Rough, coarse or
gritty
Water holding
Low water
capacity
holding capacity
Clay
Loamy
Small
Smooth and fine
Capillarity
High capillary
action
Less porous
Low but higher
than sandy
Moderate
Moderate between
sand and clay
Suitable or moderate
water holding
capacity
Moderate capillary
action
Moderate
Very high in organic
matter
Porosity
Organic matter
Low capillary
action
Very porous
Low organic
matter
High water
holding capacity
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LESSON 3: By the end of the lesson, student will be able;
o Explain soil profile
o State at least four importance of soil profile.
1.1 EXPLANATION OF SOIL PROFILE
The soil is found in layers, which are arranged during the formation of soil.
These layers called horizons.
Soil profile refers to the vertical cross-sectional view of the soil which show
the distinct layers of the soil. Soil profile differ from one place to another.
The layers of soil can easily be observed by their colour and size of
particles. The main layers of the soil are humus, topsoil, subsoil and the
parent rock. Each layer has its own characteristics.
✓ HORIZON A OR TOPSOIL
It is rich in organic material. This layer consists of decomposed material
and organic matter. This is the reason; the topsoil has a dark brown
colour. Many living organisms like earthworms, millipedes, and
centipedes, bacteria, and fungi are found in this layer of soil.
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✓ HORIZON B OR SUBSOIL
Just below the topsoil lies another layer called subsoil or horizon-B. It is
comparatively harder and compact than topsoil. It is lighter in colour
than the topsoil because there is less humus in this layer. This layer is less
organic but is rich in minerals brought down from the topsoil. It contains
metal salts, especially iron oxide in a large proportion.
BEDROCK OR HORIZON C
Bedrock is also known as parent rock and lies just below the subsoil. It
contains no organic matter and made up of stones and rocks, so it is
very hard.
Activity
1.4 finding different layers of soil
Teacher to guide pupils to dig a pit or visit a dug pit and examine and identify
the different horizons the soil profile.
QUESTIONS.
Study the diagram below carefully and answer the questions that follows.
1.Label the part A, B and C
1. Give two characteristics of each of the part label in question 1
2. Give two importance of the part labelled A.
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1.2 IMPORTANCE OF SOIL PROFILE.
✓ The depth of the top soil helps the farmer to decide on the type of
crop to grow.
✓ Soil profile helps the farmer to determine the types of tools to use on
the farm.
✓ It helps the famer to know the fertility of the soil.
✓ It also helps the farmer to know the chemical and physical properties
of the soil.
QUESTIONS:
1. Define soil profile.
2. Give four reason why farmers have to study soil profile.
SUMMARY
➢ Soil profile refers to the vertical cross-sectional view of the soil which
show the distinct layers of the soil.
➢ The main layers of the soil are humus, topsoil, subsoil and the parent
rock.
➢ The top soil is rich in humus and microorganisms, sub top soil is less in
organic matter and contains minerals. Parent rocks contains rocks and
no nutrients.
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END OF UNIT QUESTIONS
OBJECTIVE TESTS
1.
Which of the following soils is likely to be found in waterlogged area?
A. Sand
B. Gravel
C. Clay
D. Humus
2. Which of the following soil types can hold the least amount of water?
A. Clay
B. Sandy
C. Loam
D. Clay loam
3. Which of the following types of soil allows the fastest rate of drainage?
A. Loamy soil
B. Clayey soil
C. Sandy soil
D. Loamy clay soil
4. The organic part of the soil is .......
A. Mineral salt
B. Humus
C. Water
D. Air
5. The most productive soil in agriculture is ......
A. Loamy soil
B. Clay soil
C. Sandy soil
C. Silt
6. The component of the soil which is made up of the finest particles is
A. Humus
B. Clay
C. Sandy
D. Loamy
7. The proportion of sand, silt, clay and organic matter in a soil represent ....
A. Soil texture
B. Soil structure
C. Soil porosity
D. Soil capillarity
8. The colour of a fertile soil is.......
A. Brown
B. Dark brown
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C. Red
D. Yellow
9. The type of soil which feels gritty when rubbed between fingers is...
A. Clay
B. Sand
C. Humus
D. Loam
10. Clayey soil holds more water than any other type of soil because it has....
A. More porous
B. Less porous
C. Water is able to rise faster
D. Less attractive of soil particle
UNIT 3: HAZARD
LESSON 1: By the end of the lesson, student will be able to;
o Explain the term hazard.
o Give examples of hazards we encounter in teaching and learning
science.
o Give at least four causes of hazard in the teaching and learning
science.
1.1 EXPLANATION OF HAZARD
We encounter hazard everywhere in our environment, from workplace
to home and schools.
Hazard is anything or situation that has the potential or causes or harm
or danger to someone. Hazard are dangerous because it may result in
injury, diseases, loss of life and property.
1.2 SOME HAZARDS ENCOUNTERED IN TEACHING AND LEARNING SCIENCE.
✓ Fire outbreak: may be as result of poor electrical connection, faulty
electrical appliance.
✓ Falling objects: solid objects which are not properly placed may fall off
and cause accidents.
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✓ Fumes: chemical fumes and dust generated from experiments may
cause respiratory and eye irritation.
✓ Explosive substances: explosions resulting from chemical reactions in
volatile chemicals could cause fire outbreak e.g., sodium metal in
water, nitro-glycerine, hydrogen and mixture of air in the presence of
heat, dynamite.
✓ Corrosive substance; strong acids and bases can cause severe skin
burns when they come into contact with the skin. e.g., concentrated
sulphuric acid, tetraoxosulphate (IV) acid.
✓ Broken glassware: broken glassware may cause injury to the skin.
✓ Expired chemicals: drinking or tasting or inhaling expired chemicals
may be toxic to body.
✓ Inflammable substance: e.g., ethanol, petrol, LPG, propanol. etc
✓ Excessive noise: excessive noise from electronic gadgets can damage
the ear.
✓ Poisonous chemical: e.g., hydrogen cyanide, ammonia, mercuric and
lead compound.
1.3 CAUSES OF HAZARD IN TEACHING AND LEARNING OF SCIENCE
✓ Improper handling of scientific apparatus and equipment in
conducting experiment.
✓ Inadequate information about hazards.
✓ Unacceptable behaviour in the classroom and laboratory.
✓ Poor lighting in the classroom and laboratory.
QUESTIONS:
1. Explain the term hazard
2. Explain why hazard is dangerous?
3. Mention and explain four hazards that can occur in teaching and
learning science.
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SUMMARY
➢ We encounter hazards in our everyday activities.
➢ In teaching and learning science, we are expose to corrosive,
poisonous and flammable substances.
➢ Hazards impose injury and can lead to loss of life and property.
LESSON 2: By the end of the lesson, student will be able to;
Identify and interpret warning and safety signs in community and
laboratory.
WARNING AND SAFETY SIGNS IN THE LABORATORY AND COMMUNITY
Safety and warning signs in our community and laboratory can be grouped
into the following;
✓ Prohibition safety signs
✓ Mandatory signs
✓ Warning signs
✓ Occasional or safe condition signs
WARNING SIGNS
These are signs that give warning of hazard or danger. They mean caution,
risk of danger or hazard ahead. Examples of warning signs are shown below.
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MANDATORY SIGNS
They inform us to take certain actions to prevent or reduce accident.
That is, you must do or carry out the action given by the sign. Examples of
mandatory signs are shown below.
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SAFE CONDITION SIGNS
These are signs that are used occasionally.
They mean the safe way or where to go in an emergency.
Or they give information on escape route. Some examples are shown below;
PROHIBITION SIGNS
These signs mean you must not do or stop. They are used to prohibit
behaviour likely to cause accidents. they are indicated by red and
black colours. Some prohibition signs are shown below.
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Activity
1.1 identifying hazards
a) Work in groups.
b) Go around your school compound and identify potential hazards.
c) Make and design warning and safety signs to be put in those areas.
Questions.
Study carefully the following hazard symbols and answer the question that
follows.
A
B
C
D
E
G
1. What does each symbol represent?
2. Give one name of a chemical which can be associated with each
symbol.
SUMMARY
➢ Safety and warning signs can be grouped into the following;
prohibition signs, warning sign, occasional signs and mandatory signs.
LESSON 3. By the end of the lesson, student will be able to;
o Give at least five safety precautions to prevent accident in the home
o Give at least five safety precaution to prevent accident in the school.
o Identify five safety devices.
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1.1 SAFETY PRECAUTION TO PREVENT ACCIDENT IN THE HOME
✓ Clean up spills immediately. When there is a spill of liquids, grease, or
anything else you could slip on clean it up as soon as possible to avoid
falls.
✓ Keep electrical appliance dry and away from water all times and
don’t plug too electrical appliance into the same outlet at once to
prevent fire outbreak.
✓ Hot objects should not be handled with bare handles
✓ Don’t put poisonous or toxic substances in the kitchen to prevent
drinking poisonous substances or reach of children.
✓ Flammable substances like petrol, kerosene, alcohol should not be
brought near naked flame and vice versa to prevent fire outbreak.
✓ Do not put knife in water while washing your cooking utensils to prevent
cut or injury.
✓ Do not leave sharp objects on the floor to prevent cut or injury.
1.2 SAFETY PRECAUTION TO PREVENT ACCIDENT IN THE SCHOOL
✓ When performing experiment involving dilution of acid, do not add
acid to water but water to acid. This is to prevent explosion.
✓ Do not perform experiment without permission or guideline from the
teacher to prevent inappropriate and mishandling of apparatus and
chemicals.
✓ Do not walk barefooted in the laboratory because one may be
exposed to the risk of stepping on broken glassware or fallen pins.
✓ Do not open a gas tap before looking for a match to light the Bunsen
burner. This is because the gas will leak into the surrounding air and
lighting a match afterwards will cause fire outbreak.
✓ Do not run or play in the laboratory. You could break a glassware or
hurt yourself.
✓ Do not smell unknown gas with nose very close to the test tube. You
could inhale poisonous substance.
✓ Do not wash your hands with unknow liquid. This is because the liquid
may be corrosive.
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✓ Mount hazard signs or safety sign to show the various dangers
associated with the working environment.
SAFETY DEVICES
Identify and label the safety devices labelled A-G
A
B
D
E
C
F
G
QUESTIONS.
State the reasons for the following safety rules in the laboratory
1. Do not add water to concentrated acids.
2. Do not drop a large piece of sodium metal into water.
3. Close all taps before leaving the laboratory.
4. Do not walk barefooted in the laboratory.
5. Do not open a gas tap before looking for a match to light the Bunsen
burner.
6. Do not smell an unknown gas with nose close to test tube containing
the gas.
7. Do not wash your hand with an unknown colourless liquid in a beaker
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SUMMARY
➢ Hazards can be prevented by obtaining adequate information about
the chemicals and equipment we use.
➢ Safety and warning signs should be placed at potential hazards
environment.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. Which of the following chemicals is corrosive?
A. concentrate sulphuric acid
B. methane
C. Carbon monoxide
D. petrol
2. Which of the following would occur when you store inflammable
substance like LPG in science laboratory that is poorly ventilated?
A. corrosion
B. explosion
C. food poisoning
D. suffocation
3. Which of the following explains why you should not add water to
concentrated acid.
A. water becomes bitter
B. it will lead to explosion
C. it is poisonous
D. it is corrosive
4.Where would you placed a danger?
A. on potassium cyanide bottle
B. near a pit
C. filling station
D. Bleaching soap
5. Which of the following chemicals is flammable?
A. water
B. potassium cyanide
C. mercury
D. petrol
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SECTION 3: CYCLES
General Objectives:
1. recognise that there are repeated patterns of change in nature and
understand how these patterns arise
2. develop an understanding that agricultural production is cyclic in nature
3. appreciate the cyclic nature of the life of plants and its importance in crop
production.
4. develop skills in vegetable crop production.
UNIT 1: LIFE CYCLE OF FLOWERING PLANT
LESSON 1: By the end of the lesson, student will be able to;
o Define flowering plant.
o Describe the external structure of a flowering plant.
o Arrange the stages in the life cycle of a flowering plant as they occur in
nature.
1.1 FLOWERING PLANT
Flowering plants are plants that produce flowers. Examples of flowering
plants are: mango, hibiscus, okro, orange, pawpaw, guava, grasses
etc.
NB: Not all plants produce flowers. These plants are non- flowering
plants. Examples: ferns, moss, algae etc.
Activity
2.1 external structure of the flowering plant
a) work in groups
b) uproot flowering plants from the school compound.
c) Put it on the table and observe the external features.
d) Do all flowering plants have the same features?
e) Identify the root and shoot system.
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1.2 EXTERNAL STRUCTURE OF A FLOWERING PLANT.
Figure 1: the life cycle of flowering plant
All flowering plants have two main parts; shoot and root system.
The root system consists of roots.
FUNCTIONS OF THE ROOT SYSTEM
✓ It gives support to the plants
✓ It absorbs water and minerals salt for the plants
✓ Some roots serve as food storage
✓ Some roots are used for breathing (have breathing structures
called pneumatophore). E.g. white mangrove
FUNCTION OF SHOOT SYSTEM
✓ The shoot system consists of the stem, leaves, buds, flowers and
fruits.
✓ The stem holds the leaves in position, supports fruits, serves as
storage organ in some plants (opuntia and sugar cane)
✓ The leaves prepare food for the plant.
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✓ The bud develops into flower or leaf.
✓ The flowers are the reproductive part of the plant.
✓ The node is where leaves and branches develop.
1.3 LIFE CYCLE OF A FLOWERING PLANT.
Life cycle of flowering plant refers to distinct repeated pattern of changes
that occur in flowering plants to enhance reproduction. The major stages of
the flowering plant are show below;
Questions.
1. What are flowering plants?
2. Mention four examples of flowering plants.
3. Outline the various stages in the life cycle of flowering plants as
they occur in nature.
SUMMARY
➢ All flowering plants produce flowers.
➢ Flowering plants undergo repeated pattern of changes in their lifetime.
➢ The various distinct stage in the life cycle of flowering plants are;
flowering plants, pollination, fertilization, seed and fruit formation, fruit
and seed dispersal, seed germination.
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LESSON 2: By the end of the lesson, students will be able to;
o Define a flower
o Make a well labelled diagram of a complete flower.
o State the function of the various parts of a complete flower.
1.1 FLOWERING
Flower is the part of the shoot system modified for sexual reproduction.
A complete flower bears the male and female gametes. A flower is
developed from the flower bud of the flowering plant.
1.2 STRUCTURE OF A COMPLETE FLOWER.
A complete flower has
the following part;
A flower has four main
parts namely;
✓ Sepals/ calyx
✓ Petals/corolla
✓ Stamen
✓ Carpel or pistil
SEPALS OR CALYX
✓ The sepals are normally green and found at the base of the flower.
✓ They prepare food for the plant and protect the flower at the bud
stage.
✓ Some brightly coloured sepals attract insects for pollination.
✓ NB: a group of sepals is called calyx
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PETALS/COROLLA
•
Petals are large and brightly coloured part of the flower.
•
The function of the petals is to attract insects for pollination.
•
It also protects and support the inner part (whorls) of the flower.
•
A group of petals is called corolla
STAMEN (MALE REPRODUCTIVE ORGAN OF THE FLOWER
The stamen is the male reproductive organ of
the flower.
It is made of two parts namely; Anther and
filament. The anther contains the male sex
cells called pollen grains.
The filament holds the anther.
THE PISTIL (FEMALE REPRODUCTIVE ORGAN)
The pistil is made up of three parts namely;
Stigma: it is a sticky and hairy apex of the
style.
Its function is to receive pollen grains during
pollination.
Style: it’s a stalk that connects the stigma to
the ovary.
Ovary: it contains ovules.
Ovules: it contains the female cells.
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QUESTIONS
1. What is a flower
2. Study the diagram below and answer the questions that follow
a) Label the parts label A-J
b) Give the function of the part labelled A, D, F and J
LESSON 3: By the end of the lesson, student will be able to;
o Define pollination
o State the agents of pollination.
o Explain the types of pollination
1.1 POLLINATION
It is defined as the transfer of pollen grains from the anther to the
stigma of a flower. The process of pollination requires the agents
(pollinators) to move the pollen grains from the anther to the stigma.
These agents are: wind, insects, birds and human beings.
QUESTIONS: Why is pollination important in the life cycle of flowering plants.
Insect pollinated flowers are called entomophilous flowers. These
flowers have brightly coloured petals, have nectar, are easily seen,
scented and have sticky stigma.
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Wind pollinated flowers are called anemophilous flowers. These flowers
are having feathery stigma, no nectar, petals are not brightly coloured,
are not easily seen and produces a lot of pollen grains.
1.2 TYPES OF POLLINATION
There are two types of pollination namely;
1. Self-pollination
2. cross pollination
✓
Self-pollination is the transfer of
pollen grains from the anther of a
flower to the anther of the same flower
to the stigma of the same flower or
flower of the same plant. Examples
plants that are self-pollinated are pride
of Barbados, maize, coconut oil palm
etc.
✓ Cross pollination is the transfer of pollen grains from the anther of a
flower to the stigma of flower on another plant of the same species.
Examples of plants that are cross pollinated are pawpaw, sunflower,
tridax, passion flower etc.
•
Teacher will take you to the farm to observe pollination.
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QUESTIONS.
1. In your own words define pollination
2. State three pollinators of flowers.
3. Explain the two types of pollination.
SUMMARY
➢ Pollination is the transfer of pollen grains from the anther of a flower to
the stigma of a flower.
➢ Birds, insects, wind and human being are pollinators.
➢ Pollination can be self or cross pollination.
LESSON 4: By the end of the lesson, student will be able to;
o Define the term fertilization
o Describe the process of fertilization in flowering plants.
1.1 FERTILIZATION
Fertilization is the fusion of male and female sex cells to form a zygote. The sex
cells are also known as gametes.
1.2 PROCESS OF POLLINATION IN FLOWERING PLANTS.
✓ a matured pollen grain land on a
stigma
✓ pollen grain absorbs water pollen
tube and germinate to produce
pollen tube.
✓ The pollen tube elongates toward
the egg cell. The pollen is the
pathway of the egg to reach the egg
cell.
✓ The pollen tube grows toward ovary.
✓ The pollen grain divides into two; tube nucleus and generative nucleus.
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✓ The generative nucleus divides into two nuclei.
✓ One of the nuclei fuses with the ovum in the ovule.
✓ After fertilization the zygote grows an develop into embryo.
NB. The ovary matures and become fruits and the ovule develops into seed.
Activity
1. 4 fruits and seeds
a) Work in groups
b) Materials: different
kinds of fruits from
different plants, sharp
knife, petri dish and
hand lens.
c) Cut the different
kinds of fruits
longitudinally
d) Put them the halves of the fruit in the petri dish and observe with hand
lens.
e) Find the differences in the sizes and arrangement of the seeds in the
fruits.
QUESTIONS:
1. What is fertilization?
2. Explain the importance of fertilization in flowering plants.
3. Briefly describe the process fertilisation in flowering plants.
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SUMMARY
➢ Fertilisation is the fusion of fusion of the male gamete and female
gamete to form zygote.
➢ It begins when a matured pollen grains fall on a stigma.
➢ The ovule develops into a seed and the ovary of the flower develops
into fruit.
LESSON 5: By the end of the lesson, student will be able to;
o Define the term fruits and seeds dispersal
o Explain the agents of fruits and seeds dispersal
o Give four importance of dispersal of fruits and seeds.
1.1 FRUITS AND SEEDS DISPERSAL
Dispersal is the process by which plants scatter their seeds and fruits
away from themselves.
Dispersal occurs when fruits and seeds are taken away from the
parent plant by agents. These agents are; wind, water, animals and
explosive mechanism (self-dispersal)
✓ Fruits and seeds dispersed by wind are mostly small in size, dry and light
weight, some have wing -like structures and others have parachute like structure that enable them to be carried by wind.
Examples of fruits and seeds dispersed by wind are: tridax, tecoma,
dandelion, maple, combretum, orchid etc
Dandelion
tecoma
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Tridax
combretum
✓ Fruits and seeds dispersal by animals are usually edible with hard seed
testa, brightly coloured and succulent. Others have hairs and hooks.
Examples of fruits and seeds dispersed by animals are: desmodium,
guava, pepper, pawpaw, tomatoes etc.
Boerhavia
desmodium
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✓ Fruits and seeds dispersed through explosive mechanism explode when
dry. This is as result of unequal drying of the pericarp which creates
tension in it, splitting and seeding their seed away. Examples include:
crotalaria, flamboyant, balsam, okro, cowpea, acacia etc.
Flamboyant
crotalaria
okro
balsam
✓ Fruits and seeds dispersal by water are able to float and be carried by
water due to thick fibrous monocarp with a lot of air spaces. Examples
of fruits and seeds that are dispersed by water are; coconut, white
mangrove, water lotus, palm fruit etc.
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Water lotus
white mangrove
1.2 IMPORTANCE OF DISPERSAL
✓ It prevents overcrowding
✓ Controls competition of nutrient, water and sunlight.
✓ It helps in colonisation new species
✓ It helps in the survival of species
QUESTIONS:
1. What is dispersal of fruits and seeds.
2. Give three characteristics of fruits and seed dispersed by the following;
I.
Water
II.
Wind
III.
Animal
3. Give two examples each of the agents of fruit and seed listed in
question 2I, II and III
4. Give three reasons why seeds need to be dispersed.
SUMMARY
➢ Dispersal is the process whereby fruits and seeds are carried away from
their parents to prevent overcrowding, competition of nutrient, sunlight
and water.
➢ Seeds and fruits are carried by water, wind, animals and explosive
mechanism.
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LESSON 6: By the end of the lesson, student will be able to;
o Explain the term germination
o Demonstrate the conditions necessary for germination to occur.
o Explain the role of each of the condition.
1.1 EXPLANATION OF SEED GERMINATION.
Activity
1.2 structure of a bean seed.
a) Work in groups
b) Materials needed: bean seed, hand lens, petri dish and knife.
c) Split the bean seed open
d) Put two halves in a petri dish and observe with the hand lens.
You should seed the following feature as shown in the diagram below
✓ Germination can be defined as the process during which the embryo
of a seed develops into seedling.
✓ seed germination begins with the absorption of water by the seed
through the micropyle. The seed coat becomes soft. Enzymes are
activated to digest food storage and transport to the plumule and
radicle for growth to start.
✓ The plumule grows into shoot system and radicle develops into root
system.
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1.2 CONDTION NECESSARY FOR SEED GERMINATION TO OCCUR
Activity
1.5 conditions necessary for seed germination to occur.
a) Work in four (4) groups, A, B, C&D
b) Things needed: bean seeds, oil, cotton wool, test tube and rubber
tubing.
c) Set up the experiment below.
d) Put D in a freezer
e) Put the set in an open place for 6 days.
f) Observe and record your findings
QUESTIONS:
1. What happened to the bean seeds in test tube A, B, C and D?
2. Why did you put oil on top of the water in test tube C?
3. Explain why test tube D was placed in a freezer.
4. What conclusion would you make from the experiment?
✓ The conditions necessary for germination may be divided into two
forms namely;
✓ Internal conditions: enzymes and viability of seed
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✓ External conditions: moisture (water), air (oxygen) and suitable
temperature.
1.3 ROLE OF THE CONDITIONS NECESSARY FOR GERMINATION.
✓ ENZYMES: enzymes are responsible for respiration and digestion of food
storage i.e. it catalyses chemical reactions.
✓ VIABILITY OF SEED: viable seeds have undamaged embryo or lost vital
parts and free from diseases-causing organisms i.e. viable seeds have
healthy embryo.
✓ WATER (MOISTURE): water activates the enzymes and dissolves seed. It
softens the seed coat to facilitate emergence. It also serves as a
medium of transportation of dissolved food to the growing regions.
(plumule and radicle)
✓ AIR (OXYGEN): It helps in oxidation of food (respiration) to produce
energy for the seed.
✓ SUITABLE TEMPERATURE: Optimum temperature is necessary for
germination. Seed will not germinate below O0C or above 450C. Low
temperature makes the enzymes inactive and higher temperature
denature them. An optimum temperature for germination is between
28oC and 37oC.
✓ NB. The minimum temperature required by all seeds before germination
can occur is called optimum temperature.
SUMMARY
➢ Germination is the process whereby the embryo of a seed develops
into seedlings.
➢ The conditions necessary for germination to take place are: viable
seed, suitable temperature, enzymes, air(oxygen) and moisture.
➢ A viable seed is a seed with healthy embryo.
➢ The enzymes digest food and water activate enzymes in the seed
to germinate.
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END OF UNIT QUESTIONS
OBJECTIVE TEST
1. A fertilised ovule results in the formation of .......
A. Embryo
B. Stigma
C. Pistil
D. Ovary
2. Which of the following is not an agent of dispersal?
A. birds
B. Water
C. wind
D. carbon dioxide
3. The stamen of a flower is made up of ……
A. anther and filament
B. anther and style
C. filament and stigma
D. style and stigma
4. The outer coat of a seed is …...
A. testa
B. micropyle
C. cotyledon
D. plumule
5. Which of the following stages occur after pollination?
A. fertilization
B. germination
C. dispersal
D. fruit and seed maturation
6. The embryo of a seed consist of the………
A. plumule and radicle
B. plumule and cotyledon
C. plumule and cotyledon
D. radicle and micropyle
7. The petals of a flower is collectively called…...
A. receptacle
B. calyx
C. corolla
D. stamen
8. A viable is seed is a……...
A. death seed
B healthy seed
D. deformed seed
C. wet seed
9. Which of the following is not a condition necessary for germination to
occur?
A. water
B. light
C. oxygen
D. suitable temperature
10. The part of the flower that protects the flowers at the bud stage is
called……...
A. petals
C. sepals
B. pedicle
D. stigma
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UNIT 2: VEGETABLE CROP PRODUCTION
LESSON 1: By the end of the lesson, student will be able to;
o Describe the principles of crop production.
PRINCIPLES OF CROP PRODUCTION.
In order to grow crops successfully, it is important to understand the principles
of crop production.
Principle of vegetable crop production is an act that ensures the long-term
productivity of the land, by protecting the health of soil, water, air and
biodiversity.
OR
The term principle of crop production is certain laid down processes or
procedures that one should follow to be able to produce crops and obtain
higher yield. These principles are outlined below;
✓ Land selection: it important to select the appropriate land for crop
production because each type of crop grows best in a specific type
of soil. for example, maize requires a well-drained loam soil to grow
whilst groundnut requires sandy loam soils.
This means that, the land selected for crop production must be fertile
and healthy for crop growth.
✓ Land preparation: Your land must be properly prepared for
vegetable crop production. Land preparation depends on the type
of land of the selected site; that is whether the land is grassland or
forestland. Preparing land involves clearing, tilling and ridging.
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Figure 1.1 a farmer preparing the land for crop production
✓ Selection of varieties: This involves the use of healthy seeds or
planting materials in vegetable crop production.
It also includes selecting different types of a particular crop for a
particular reason. For example,
Cassava has many varieties. There are those for making industrial
starch (high starch) and ones processed into gari
✓ Method of propagation: It is important to use the appropriate
method to grow vegetable.
There are two ways or methods of propagation. These are;
Sexual propagation (seeds)
This is a type of propagation in which seeds are used. examples okro,
tomato, sorghum, rice etc.
Some vegetable crops such as cabbage, tomatoes and pepper, the
seed are raised in a nursery and transplanted later on to the field.
Others, for example okro, cucumber, French beans are sown directly
into the soil without first nursing them. we call this ‘planting at stake
Vegetative propagation (part of plants)
This is the use of parts of plants for propagation other than seeds.
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Parts of plants that can be used for propagation include leaves, roots
and stems. There are two types of vegetative propagation;
•
Natural vegetative propagation: It is a type of vegetative propagation
where parts of t plants are put directly into the soil and they grow into a
matured plant looking exactly like the parent plants.
Most of these plant’s parts have buds that grows into a new plant.
Examples of natural vegetative propagation:
Leaf buds:
Examples: Bryophyllum and Begonia
Bryophyllum
begonia
Suckers
examples: plantain, pineapple, banana
Pineapple sucker
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Runners
examples: sweet potato
Rhizome
examples: ginger, canna lily
Canna lily
ginger
Bulbs
examples: onion and garlic
Garlic
onion
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Corms
examples: cocoyam and caladium
Stem tubers
examples: yam and sweet potato
Artificial vegetative propagation
This is a type of vegetative propagation in which human being grows
plants with desirable characteristics using their parts.
Methods used to artificially propagate are;
Grafting, budding, layering, marcotting and tissue culture
Grafting: It is the process of joining the part of the plant to be
propagated (scion) onto another plant (stock) on the same species.
QUESTION: Give three advantages of natural propagation over artificial
propagation.
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Grafting
layering
marcotting
budding
SUMMARY
➢ In order for a farmer to get good yield of vegetables and ensure long
term soil productivity, he has to select a good land, prepare the land,
select the right varieties and choose the appropriate method for
propagation.
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LESSON 2: By the end of the lesson, student will be able to;
o Give at least four difference between sexual and asexual
propagation.
o Describe at least five cultural practices in crop production.
1.1 DIFFERENCE BETWEEN SEXUAL AND ASEXUAL PROPAGATION
Sexual propagation
Asexual propagation
1. It requires two parents
It requires one parent
2. Offspring are not identical
Offspring are identical
3. Embryo is formed
No embryo is formed
4. It involves fertilization and
pollination
It does not involve pollination
and fertilization.
1.2 CULTURAL PRACTICE
Cultural practices are the activities that are performed on the farm,
after planting till harvest time.
Activities include;
Weeding: it is the act of removing weeds from the farm. Weeds can be
removed by cutting, hoeing, mulching and application of chemicals
called herbicide.
QUESTION: Why do we have removed weeds from the farm?
Application of fertilizer
Vegetable crop can benefit from fertilizer if the soil they are growing is
not very fertile. Fertilizers may be organic or inorganic. Inorganic
fertilizer like sulphate ammonia and NPK (Nitrogen, Phosphorus,
Potassium) are essential for vegetable crop production.
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Mulching: it is the practice of covering the surface of the soil with
organic materials like straw, dead grass, dry leaves etc.
QUESTION: Why is mulching important?
Pest and disease control
Pest and disease can be controlled in several ways;
Practice crop rotation to make sure that diseases do not complete
their cycle and attack other crops
Weed vegetable crop regularly.
Pests like birds, grasscutters and rat
can be controlled by using scarecrows.
Spray diseases and pests with
chemicals when the attack is bad.
QUESTION: Why do you have to
control pests and diseases?
Earthing up
It is the process of heaping top soil
around the base of a stem of a
plant.
QUESTION: Why is earthing up
important?
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Pruning
It is the act of removing excess
branches and flower buds and
also other parts of the plant that
are affected by diseases.
QUESTION: Why is pruning
important?
Staking
It is the act of supporting a crop
with weak stem with a pole or
stick so that it grows upright.
Examples of crops that can be
staked are: yam, tomato, beans,
etc.
QUESTION: Why staking
important?
HARVESTING AND STORAGE
Crops must be harvested
as soon as they mature.
If matured crops are left
unharvested in the field
they will spoil and are
also likely to be attacked
by pests and diseases.
Crops need to be stored
at the right place with
suitable temperature so
that they don’t get bad
readily.
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PROCESSING AND MARKETING
Processing means changing
agricultural produce from
the raw form to other forms.
Why do we have to process
agricultural produce?
Vegetable crops can be
processed in various ways,
such as freezing, canning,
drying, salting, milling.
SUMMARY
➢ Cultural practices are the activities that are carried out in the farm
after planting till harvesting.
➢ Some activities carried out are; weeding, pruning, watering, mulching,
staking, earthing up and harvesting
LESSON 3: By the end of the lesson, student will be able to;
o Define the term nursery in vegetable crop production
o Describe activities that are carried out in the nursery.
RAISING SEEDLINGS IN NURSERY BEDS
Nursery bed is small portion of the land prepared to raise seedlings for
planting. Nursery beds are beds about 1-metre-long and 1 meter wide.
There are two types of beds;
Raised bed; this is a bed that
is raised above the
surrounding ground.
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Sunken beds
These are beds that sunk
below the surrounding
ground.
Vegetable can be sown in the nursery bed by drilling or broadcasting.
Drilling method is when a small hole is made with dibber or a pointed
stick and a viable is put in the hole and covered with soil.
Broadcasting method: This involves spreading the seeds all over the
bed as evenly as possible and covering the seeds with thin layer of
topsoil.
QUESTION: What are the advantages of drilling method over
broadcasting?
CULTURAL PRACTICE IN THE NURSERY.
✓ Weeding: it the removal of
unwanted plant from farm. Weeds
should not be allowed to grow in
the nursery. They must be removed
immediately they appear to prevent competition of nutrients, water,
space and sunlight. Weeds can be removed by carefully uprooting
them.
✓ Watering / irrigation: it the process of artificially supplying sufficient
water to plants. Source of water must be close to the nursery bed.
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Irrigation should be done in the morning or evening when the sun is
not too hot.
✓ Thinning out: it is the removal of excess seedlings from the nursery
bed to enhance healthy growth for other. In thinning out weak
seedlings are also removed. Thinning out prevent competition of
nutrients, sunlight and water.
✓ Hardening off- it is preparing seedlings to adapt to the conditions
that exist in the seedbed 1-2 weeks before transplanting. During the
period of hardening off, watering should be reduced so that
seedling will be able adapt when they are transplanted.
✓ Shading- to maintain cool
temperatures for proper seedling
growth. Light shade to prevent dark
conditions that may encourage
etiolating of seedlings.
SUMMARY
➢ Nursery is a small portion of the land where seedlings are raised
before planting.
➢ Some activities carried out in the nursery are; shading, thinning
out, weeding, irrigation and hardening off
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LESSON 3: By the end of the lesson, student will able to;
o Define vegetable crop.
o Give at least five examples of vegetable crops.
o Describe the factors in vegetable crop production.
1.1 VEGETABLE CROP
Vegetables are edible plants grown for their leaves, fruits, stems, seeds
and flowers and usually eaten along with other main staples.
Examples of vegetable
include: onion, lettuce,
Spanish, cabbage, garden
eggs, carrot, tomato,
cauliflower, cucumber etc.
1.2 FACTORS IN VEGETABLE CROP PRODUCTION
Factors to consider before one decides to grow vegetables are;
✓ Climatic Factors: climatic factors include; rainfall, temperature, wind
and light. You need to select a vegetable crops for production that
suit the temperature, rainfall pattern, wind and light of the selected
site. Tomato requires a temperature of 200C-300C and does not
need high temperature and excessive rainfall.
✓ Nearness to Source of Water: The selected site should contain
adequate water for vegetable production. It is also important for
vegetable crop production should be near to source of water of
sufficient quality to irrigate the crop when necessary.
QUESTION: Why is quality of water important in vegetable production?
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✓ Soil Factors
Different kinds of crops grow in different types of soil.
Ideal soils for vegetable crop production are well drained sandy loam
soil. The soil should be fertile and rich in humus.
✓ Nearness to Source of Water: Vegetable crops need enough water to
grow well. Therefore, the selected site should contain adequate
water for vegetable production. It is also important for vegetable
crop production should be near to source of water of sufficient
quality (free from toxic and poisonous substance) to irrigate the
crop when necessary.
QUESTION: Why is quality of water important in vegetable production?
✓ Nearness to Markets
Vegetable crops should be harvested as soon as they mature. This is
because most vegetables are perishable and can spoil quickly,
vegetable farms should be near to market place where they will be
sold.
SUMMARY
➢ Some examples of vegetables are; onion, cabbage, okro ,
tomatoes, lettuce, carrot etc.
➢ Things to consider when growing vegetables are: climate of the
area, sources of water, good and fertile soil and nearness to
market
LESSSON 4: By the end of the lesson, student will be able to;
o Explain how tomato is cultivated
o Give at least four importance of vegetable crops production.
1.1 CULTIVATION OF TOMATO
Tomato is one of the most widely grown vegetables in the world because of it
varied uses. Tomato re well require well-drained loamy soil rich in organic
matter. soil because they are sensitive to waterlogging.
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In cultivation of tomato, you must choose the right variety, produce seedlings
by nursing the seed, tomato requires optimal soil temperature of 200C- 300C,
prepare the land by weeding, tilling and making ridges. Hardening off
seedling should be done for 1-2 weeks before it transplanted.
Cultural practices like watering, weeding, fertilizer application, pest and
diseases control and staking should be undertaken.
Tomato can be harvested at different stages, depending upon the time
needed to market the fruit. For long distance transport, fruit can be harvested
at the breaker stage (not more than 10% of the surface is tannish-yellow, pink,
or red). Fruit for local sale can be harvested at later ripening stages.
Tomatoes at different stages of growth.
IMPORTANCE OF VEGETABLE CROPS TO HUMANS
✓ Vegetables serve as a source of food
✓ Vegetable production serve as employment
✓ Some vegetables are used for medicinal purposes, e.g. garlic.
✓ Vegetables are rich in vitamins and mineral prevent and protect the
body from infections.
✓ Some vegetables are rich in fibres/ roughages that help in digestion
and prevent constipation.
✓ Vegetables production serve as a source of income when produced
for commercial purposes.
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SUMMARY
➢ Tomato grows well in a well-drained loamy soil rich in organic matter.
Some activities to carry out when cultivating tomato are; watering,
weeding, fertiliser application and staking.
➢ Vegetables serve as source of food and employment.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. Which of the following vegetable crops is staked?
A. okro
B. carrot
C. tomato
D. onion
2. The process of covering the surface of the soil with organic materials is term
as…………………….
A. weeding
B. earthing up
C. mulching
D. covering
3. Which of the following is not practised on the nursery?
A. watering
B. thinning-out
C. weeding
D. pruning
4. The practice of removing excess branches, flower buds and infected parts
of the plant is referred as ………………..
A. pruning
B. cutting
C. weeding
D. clearing
5. The term transplanting as used in vegetable crop production means………
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A. planting seeds directly into the soil.
B. transferring healthy seedlings from the nursery bed to the main field
C. carrying manure from one place to another
D. removing weak and extra seedling from the nursery bed.
6. Which of the following is propagated by using rhizome?
A. onion
B. cocoyam
C. ginger
D. plantain.
7. Earthing up is a practice of ……………………...
A. covering the surface of the soil with organic materials
B. heaping soil the base of the stem of a plant
C. covering a seed in a hole
D. applying fertilizer to the soil
8. The term ‘planting at stake’ means……………………...
A. sowing seed directly into to the soil without nursing
B. planting with sticks
C. planting without carrying out any cultural practice
D. planting with stakes
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SECTION 4: SYSTEMS
General objectives
❖ recognise that a system is a whole, consisting of parts that work
together to perform a function
❖ show an understanding of the role of the respiratory system of humans
❖ appreciate the basic principles underlying various farming systems.
UNIT 1: FARMING SYSTEMS
LESSON 1: By the end of the lesson, student will be able;
o define farming.
o Give four importance of farming to the society.
o List at least five farming systems practiced in Ghana.
o Explain land rotation as farming system.
o Give at least three advantages and disadvantages of land rotation.
o Explain crop rotation.
1.1 FARMING
It is the act or process of growing crops and rearing of animals for food and
raw materials.
1.2 WHY IS FARMING IMPORTANT?
✓ it provides food for human consumption.
✓ It serves as a source of raw materials to major industries such as cotton
and jute fabric, sugar, tobacco, edible as well as non-edible oils is
agriculture.
✓ Farming provide employment for great number of people.
✓ It serves as a source of foreign exchange resources.
✓ Farming serves as a source of revenue for the country.
Farming system refers to the various methods which are used to produce
crops or animal products. In Ghana, various farming system are practiced.
They include;
Mixed farming
Monocropping
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Monoculture
Land rotation
Mixed cropping
Shifting cultivation
Organic farming
Pastoral farming
Crop rotation
ecological farming
1.3 EXPLANATION OF THE VARIOUS FARMING SYSTEM
Land rotation: this is a farming system in which a farmer cultivates a piece of
land for some time and then leaves to cultivate a new land when the fertility
of the old land is lost without moving his family and settlement.
Advantages and disadvantages of land rotation
Advantages of land rotation
Disadvantages of land rotation
The farmer always has a
The virgin forest is destroyed.
fertile land on which to farm.
The old farmlands have
It cannot be practice where land is
enough time to become
scarce
fertile again.
Pests and diseases are
Constant clearing of new lands for
controlled
farming involves a lot of work and
expenses.
Crop rotation
It is a system of farming where a farmer keeps just one farm but grows
different types of crops on different portions or plot of the farmland in a
definite sequence or order.
Each growing season, the farmer rotates the crops so that the same crops do
not grow continuously on the same plot of land.
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When practising crop rotation, certain guidelines or laid rules must be
followed. These guidelines are outlined below;
✓
Crops with deep roots should be
followed by crop with shallow roots.
Example, cassava (deep root) should
be followed by cowpea (shallow root)
✓
Crops that belong to the same
family should not follow each other in
the rotation. Example, millet should not
follow maize.
✓ Leguminous crops like cowpea and groundnut should be included in
the rotational plan. Leguminous crops fix nitrogen into the soil, improves
soil structure, check soil erosion and control weed growth.
✓ Do not grow crops that are susceptible to the same pests and diseases
after each other. For example, do not grow okro after cotton
✓ Fallow period should be allowed during the time of rotation.
The table below shows four-year crop rotation programme using maize,
cowpea, cassava and tomato.
SUMMARY
➢ Farming provides food for human consumption.
➢ Land rotation cannot be practiced in an area where land is
scarce because the farmer cultivates new land when the old
one loses its fertility.
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➢ Crop rotation make efficient use of the land and the fertility of
the soil is maintained because the farmer rotates the crops in
sequence and leguminous crops are included.
LESSON 2: By the end of the lesson, student will be able to;
o Draw a three-year crop rotation programme.
o Give at least three advantages and disadvantages of crop
rotation.
o Explain the term mixed cropping
o Give at least three advantages and disadvantages of mixed
cropping.
1.1 Table showing a three-year crop rotation programme
Farmland divided
into three plots
Year 1
Year 2
Year 4
Plot 1
Yam
Groundnut
Maize
Plot 2
Groundnut
Maize
Yam
Plot 3
Maize
Yam
Groundnut
Table showing a four-year crop rotation programme
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Farmland
Year
divided
1
Year 2
Year 3
Year 4
into four
plots
Plot 1
Maize
Yam
Cowpea
Cassava
Plot 2
Cassava
Maize
Yam
Cowpea
Plot 3
Cowpea
Cassava
Maize
Yam
Plot 4
Yam
Cowpea
Cassava
Maize
QUESTIONS
1) Use the following crops to draw a three-year crop rotation plan;
maize, cowpea and cassava
2) Explain why soya bean is included in the programme.
3) Give three differences between land rotation and crop rotation.
1.2 ADVANTAGES OF CROP ROTATION
✓ Farmer gets different kinds of crops from the same field.
✓ Soil fertility is maintained because of inclusion of leguminous plants
✓ Pests and diseases are controlled
✓ It provides economic use of land.
Disadvantages of crop rotation
✓ It requires special skills.
✓ It is difficult since the farmer has to grow different crops.
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1.3 MIXED CROPPING
This is a farming method in which the
farmer grows two or more kinds of
crops on the same piece of land at
the same time.
For example, the farmer may grow
maize, tomatoes, okro and pepper
all mixed together on the same
piece of land.
Advantages of mixed cropping
✓ The farmer gets different crops from the same field.
✓ If one crop fails, the farmer will still have other crops from the same
field.
✓ It helps to check erosion because different crops produce a lot of
leaves to cover the soil.
✓ If leguminous crops are grown, they help to improve soil fertility
✓ The farmer gets a lot of income.
✓ Farmer gets crop throughout the season since different crops are
harvested at different times.
Disadvantages of mixed cropping
✓ The soil can lose it fertility very quickly.
✓ Some crops may grow better than others because of competition of
nutrients.
✓ More work is involved in taking care of different crops on the same
field.
QUESTION
Give three differences between land rotation and mixed farming.
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SUMMARY
➢ In crop rotation, shallow rooted crop follows deep rooted crop.
➢ Soya beans is included in crop rotation plan to improve soil fertility.
➢ In mixed cropping, the farmer gets different kinds of crops at the same.
LESSON 3: By the end of the lesson, student will be able to;
o Define mixed farming
o Give at least three advantages and disadvantages of mixed farming
o Define organic farming
o Give at least three advantages and disadvantages of organic farming.
1.1 MIXED FARMING
This is a farming system in which the farmer produces crops and rear animals
on the same piece of land. For example, the farmer may grow maize and
rear cattle on the same piece of land. In mixed farming the livestock are
prevented from destroying the crops by housing them.
Advantages of mixed farming
✓ The farmer obtains both crops and meat from the farm.
✓ Manure from the livestock can be used to fertilise the crops.
✓ the farmer has more source of income.
✓ Where cattle are raised, the farmer can use some of the bullocks for
ploughing and transportation.
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Disadvantages of mixed farming
✓ The farmer needs knowledge of both crops and animals
✓ The farmer work throughout the year.
✓ When animals are not well confined, the crops can be destroyed.
1.2 ORGANIC FARMING
It is a farming system in which natural processes are used to produce crops
without harming the environment.
In organic farming no chemicals are used. Natural process such as crop
rotation, mulching, manuring, composting, biological pest control method,
plant resistant to pest and diseases are used.
Advantages of organic farming.
✓ Farmer gets good yields from season to season because the land
remains fertile.
✓ the food produced is healthier because no chemical is involved.
✓ The environment is protected from pollution.
✓ It improves soil structure.
✓ Organically grown crops are able to tolerate drought.
Disadvantages of organic farming
✓ Organic farming is labour intensive.
✓ it requires special skills.
✓ It is labour intensive.
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QUESTION
Give three difference between organic farming and crop rotation.
SUMMARY
➢ In mixed farming, the farmer gets both plant and animal products.
➢ Organic farming does not pose any harm on the environment
because, sustainable agricultural practice and natural processes are
used.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. The farming system in which two or more crops are grown on the same
piece of land at the same time is referred as………………………...
A. crop rotation
B. monocropping
C. mixed farming
D. mixed cropping
2. Leguminous crops are included in crop rotation to ………………….
A. fix nutrient into the soil
B. prevent soil aeration
C. to prevent the activities microorganisms in the soil
D. scare pests
3. Which of the following is a leguminous crop?
A. tomato
B. cowpea
C. cassava
D. maize
4. Which of the following crop would you plant after cassava?
A. Yam
B. Sweet potato
C. soya beans
D. cocoyam
5. The farming system in which sustainable agricultural practices and organic
materials are used is called………………….
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A. crop rotation
B. organic farming
C. mono cropping
D. mixed farming
6. Which of the following is a deep-rooted crop?
A. maize
B. yam
C. soya beans
D. rice
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UNIT 2: RESPIRATORY SYSTEM OF HUMANS
LESSON 1: By the end of the lesson, student will be able to;
o Define the term respiration
o Briefly describe how respiration take place in human
o explain the types of respiration
o Write a word equation to represent aerobic respiration
o State at least four difference between aerobic respiration and
anaerobic respiration
1.1
RESPIRATION
Where do get energy from? Energy is obtained from the food that we eat. All
living things need energy for activities such as walking, running, reproduction
etc. This energy is locked up in the food we eat.
After digestion, energy in the food is obtain by a process known as
respiration.
Therefore, respiration can be defined as the chemical process whereby food
(glucose) is broken down to release energy either in the presence of oxygen
or absence of oxygen.
Glucose is the fuel that provides energy in living organisms. Respiration is not
the same breathing but they are related. Every cell needs oxygen survive.
Breathing provides oxygen for breaking down the food to release energy.
The energy produced is required for cellular process like; cell division,
movement etc. During respiration, heat is produced and it helps to living
organisms to maintain optimal temperature.
1.2 TYPES OF RESPIRATION.
There are two types of respiration.
These are;
✓ Aerobic respiration
✓ Anaerobic respiration
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AEROBIC RESPIRATION
This a type of respiration that takes place in the presence of oxygen.
During breathing in humans, cells use oxygen to break down food to release
energy. At the same time, the process releases carbon dioxide and water.
Excess carbon dioxide must be removed immediately, because excessive
amount of carbon dioxide produces acidity that can be harmful or toxic to
the cell.
Glucose + Oxygen → Carbon dioxide + Water + Energy
C6H12O6 +
6O2
→
6CO2 + 6H2O + Energy
QUESTIONS:
Respiration is a chemical reaction that happens inside cells.
a. Copy and complete the word equation for respiration.
glucose + ...................... → carbon dioxide + ........................+……………...
b. This reaction is known as aerobic respiration.
c. Explain why it is described as ‘aerobic’.
ANAEROBIC RESPIRATION
This type of respiration takes place without using oxygen.
Imagine sprinting 100 metres. You need to transfer energy from glucose to
your muscles very quickly. However, your body cannot get oxygen to its
muscles quickly enough for aerobic respiration to occur. This is why anaerobic
respiration happens instead.
In humans, anaerobic respiration produces lactic acid as a by-product.
In plants and yeast, alcohol and carbon dioxide are produced as byproduct.
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1.3 DIFFERENCES BETWEEN AEROBIC AND ANAEROBIC RESPIRATION
Aerobic respiration
Anaerobic respiration
Oxygen is used up in the process
Oxygen is not used up in the
process
Large amount of energy is released
Less amount of energy is released
Water and carbon dioxide are
produced as waste products
No water or carbon dioxide are
produced as waste products
No lactic acid or alcohol is
produced as by-product
Lactic acid or alcohol is produced
as by product
LESSON 2: By the end of the lesson, student will be able to;
o Define the term respiratory system
o Give at least four characteristics of respiratory organs
o Identify the various structures of the human respiratory system
o State at one function each of the structures identified
SUMMARY
➢ Living organisms need energy to survive.
➢ The cells obtained energy from glucose in a chemical reaction called
respiration.
➢ In aerobic respiration, oxygen combines with glucose. Carbon
➢ dioxide and water are produced.
1.1 THE HUMAN RESPIRATORY SYSTEM
The human respiratory system consists of various organs that work together to
provide oxygen for respiration to take place i.e. organs that help to get
oxygen from the air into your blood, and to get rid of carbon dioxide, make
up the respiratory system.
Different organisms have different organs for providing oxygen for respiration.
Some use their lung and skin, mouth, gills and trachea.
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In human, the respiratory system consists of the nose, nasal cavity, pharynx
larynx, trachea, bronchi, bronchioles and alveoli.
1.2 CHARACTERISTICS OF RESPIRATORY ORGANS
✓ All organs for exchange of gases have the following features;
✓ Have moist surface that facilitate gaseous exchange.
✓ Have large surface area to facilitate exchange of gases.
✓ Consist of thin wall cells or membrane for easy diffusion.
✓ They are highly vascularised.
1.3 ROLE OF THE HUMAN RESPIRATORY ORGANS.
Nose: Air is breathed in and out through the nose. It contains hair-like
structures that filter out large dust particles.
Nasal cavity: it contains fine hairs called cilia and a secretion called mucus
that trap dirt, dust particles and microscopic organisms from the air. The
nasal cavity has structures that warm and moisten the breathed air.
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Pharynx: This is a common passage for food, water, and air. It leads from both
the nose and the mouth and leads to both the trachea (windpipe) and the
oesophagus.
Epiglottis: it is a sheet or flap of tissue that closes the entrance into the
trachea during swallowing to prevent food from entering the respiratory tract.
Larynx (voice box): it is the region that the ‘Adams apple’ lies.
It contains mucus and cilia that help to filter the air. It contains
strings of different sizes that help to produce sound.
Trachea (windpipe): it contains mucus and cilia that filter
dirt, dust particles and germs from the air. It also moistens
and warms the air breathed in. The trachea split into two
short tubes knows as the bronchi.
Bronchi: they serve as passage of air. They also filter,
moisten and warm the air. The bronchi branch into
smaller tubes called bronchioles.
Bronchioles: they contain cilia and mucus that filter the
air. They end in a lot of air sacs called alveoli.
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Air ends its pathway in the alveoli (sing. alveolus) which are tiny sacs with very
fine single-celled walls. These alveoli are surrounded
by capillaries that enable exchange of oxygen.
Activity: demonstrating respiration in living organism(pea)
a) Work in groups
b) Material needed: boiled pea seed, soaked pea seeds, vacuum flask,
thermometer and cotton wool.
c) Set up the experiment below
e. Observe the temperature in the two flask and record your observations
f. did you see a change in the temperature of the flask containing the
dead seeds? If No, explain
e. Take the temperature of the two flasks at different time intervals and
record your findings in a table form.
SUMMARY
➢ Hair, cilia and mucus filters the air breathed in.
➢ Exchange of gases occur in the alveoli of the lungs through diffusion.
➢ Epiglottis prevents food from entering the trachea when food is
swallowed
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LESSON 3: By the end of the lesson, student will be to;
o define breathing or gaseous exchange
o describe the mechanisms of breathing
o state at least four diseases associated with the human respiratory
diseases.
1.1 MECHANISM OF BREATHING OR EXCHANGE OF GASES IN HUMAN
Breathing is the process through which air get in and out of the body.
Breathing involves two process;
Breathing-in (inhalation)
Breathing-out (exhalation)
Apart from the respiratory organs in humans, the ribs, intercostal muscles and
the diaphragm help in breathing.
What happens during breathing- in:
Intercostal muscles contract.
Ribs move upward and outward.
Diaphragm attains flattened position.
Volume of thoracic cavity increases.
Pressure reduces in the thoracic cavity.
Air is rushed into the lungs.
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Breathing -out
Ribs move downward and inward.
Diaphragm returns to its original position
(domed shape) position.
Volume of thoracic cavity decreases.
Pressure increases in the thoracic cavity.
Air is rushed out the lungs.
QUESTIONS
1. study the diagram of the human respiratory system below and answer the
questions that follow.
a. Name structures labelled 1-11.
b. state the function of the structures
labelled 1, 3,8 and 11
c. state four diseases of the human
respiratory system.
1.2 SOME DISEASES ASSOCIATED WITH THE HUMAN RESPIRATORY SYSTEM
smoking produces carbon monoxide that reduces the
oxygen capacity of the blood. Tar in cigarette causes lung
cancer and other related cancers. Particulates damage
the surface of the lungs. Nicotine in cigarette is addictive.
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Other respiratory diseases are: whooping cough, pneumonia, tuberculosis,
influenza, bronchitis etc.
SUMMARY
Breathing provides oxygen for respiration and gets rid of unwanted
➢
gas from the body.
➢ Breathing include; inhalation and exhalation.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. What is the name of the tiny sacks in the lungs of the human respiratory
system?
A. bronchi
B. alveoli
C. bronchioles
D. cilia
2. Which of the following statement is true during breathing in
A. the volume of the thoracic cavity decreases
B. the volume of the thoracic cavity increases
C. the diaphragm moves to its original position
D. air is rushed out of the lungs
3. The trachea is also known as…………………
A. Adam’s apple
B. windpipe
C. air sacks
D. breathing tube
4. Which of the following systems is responsible for taking in and out air?
A. excretory system
B. reproductive system
C. respiratory system
D. nervous system
5. Which of the following serves as a fuel for respiration to take place?
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A. glucose
B. oxygen
C. carbon dioxide
D. water
6. When you breath in, your lungs……………….
A. deflate
B. inflate
C. turn purple
D. disappear
7. What is the function of the tiny hairs inside your nose?
A. absorb oxygen
B. trap dust particles
C. fight against diseases
D. allow more air to enter the lungs
8. Which of the following statement about aerobic respiration is true?
A. large amount of energy is produced
B. it takes place in the absence of oxygen
C. alcohol is produced as by-product
D. glucose is not needed to produce energy
9. The trachea divides into two smaller tubes called……………...
A. oesophagus
B. bronchi
C. epiglottis
D. eustachian tube
10. The process of taking in air from the atmosphere and taking out from the
lungs is known as………...
A. internal respiration
B. external respiration
C. tissue respiration
D. cellular respiration
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SECTION 5: ENERGY
General Objectives:
✓ recognise that energy has a source, can be transformed into
various forms
✓ be aware of renewable and non-renewable sources of energy.
✓ understand the transformation pathways of various sources of
energy.
✓ understand the mechanics of and the use of LEDs, diodes,
resistors and capacitors
✓ be aware of some of the characteristics and uses of light energy.
UNIT 1: SOURCES OF ENERGY
LESSON 1: By the end of the lesson, student will be able to;
o define the term energy.
o state the sources of energy.
o Define the term renewable resources.
o Give examples of renewable sources of energy.
1.1 ENERGY
We work every day and every activity
we do requires energy. Energy
cannot be separated from the things
we do.
When we eat food, our body uses
energy locked up in the food to
move around.
When we switch on the TV, electricity
is used to create the picture on the screen and the sound.
Energy can be defined as the ability of a body to do work.
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Every time something gets warm, cools down, moves, grows, makes a sound
or changes in any way, it uses energy. What about a piece of paper sitting
on a desk not moving? The paper still has energy – it is just not using it.
Energy is measured in joules(J)
1.2 SOURCES OF ENERGY.
Energy sources can be grouped broadly into two;
✓ Renewable sources of energy.
✓ Non-renewable sources of energy.
1.3 RENEWABLE SOURCES OF ENERGY.
Renewable sources of energy are those that can be replenished within a
short period of time.
These sources of energy are in continuous supply.
1.4 EXAMPLES OF RENEWABLE SOURCES OF ENERGY.
✓ The sun or solar energy: solar energy is the energy obtain from the sun.
solar energy is tapped and converted and used for domestic and
other purposes such as heating water, cooking food, electricity using
photovoltaic cells.
Solar panel
solar torch
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Wind energy
Wind is converted to electricity using to a device called windmill. Huge fans
are installed to harness wind energy.
windmills
Biomass energy
Biomass is organic material made from plants and animals.
Biomass is a renewable and sustainable source of energy, it can either be
used directly via combustion to produce heat, or indirectly after converting it
to various forms of biofuel.
Biomass can be converted to other useable forms and used for energy such
as:
✓ Agricultural crops and waste materials—burned as a fuel or fermented
to produce liquid biofuels such as ethanol.
✓ Animal manure and human sewage—converted to biogas such as
methane, which can be burned as a fuel.
Water energy
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This energy is obtained from moving
water and tidal waves.
The movement of the water turns the
blades of a turbine, which is connected
to a generator to generate electricity. In
Ghana huge amount of energy is
generated from Akosombo dam.
Geothermal energy
This is energy generated and stored in the hot
core of the earth. This is tapped and used to
heat water and generated to produce
electricity.
Geothermal plant
SUMMARY
➢ Energy is the ability of a body to do work
➢ Renewables sources of energy can be replenished within a short period
of time
LESSON 2: By the end of the lesson, student will be able to;
o Define the term non-renewable sources of energy.
o Outline four examples of non-renewable sources of energy.
1.1 NON- RENEWABLE ENERGY SOURCES OF ENERGY
Non-renewable sources of energy are the sources of energy that cannot be
replenished in a short period of time.
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These energy sources have limited lifetime i.e. they are not in continuous
supply.
Fossil fuels provide the greatest energy for humankind. These energy sources
are formed from buried remains of plants or animals that died millions of years
ago.
Heat and pressure gradually turn the dead remains of plant and animals into
fuel. It is a non-renewable resource because it comes from carbon-based
organic matter that is difficult to replace or takes a long time to be
replenished
Fossil fuels include; coal, crude oil, and natural gases.
Crude oil /petroleum: We drill through the earth to access the oil. Some
deposits are on land, and others are under the ocean floor. Once the oil has
been drilled, it must be refined. It refined through fractional distillation.
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Natural gas
Natural gas is another fossil
fuel that is trapped
underground in reservoirs. It
is mostly made up of
methane. You may have
smelled methane before.
The decomposing material
in landfills also release
methane, which smells like
rotten eggs.
We use natural gas for heating and cooking. Natural gas can also be
burned to generate electricity. We rely on natural gas to give power to
lights, televisions, air conditioners, and kitchen appliances in our homes.
Natural gas can also be turned into a liquid form, called liquid natural
gas
Coal:
Coal is a fossil fuel created from the
remains of plants and animals that lived
and died millions of year ago. It is darkbrown to black solid material. Coal
produces electricity when it is burnt in a
broiler to produce steam. The steam turns
turbines which generate electricity.
Uranium
The material most often used in nuclear power plants is the element uranium.
Uranium produces electricity through nuclear fission.
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Project Work: Design and Construct a biodigester.
•
Materials needed: two empty oil drums with different sizes (one should
be able to fit into the other), rubber tube, adhesive, animal wastes
(cow dung or poultry droppings)
• Biodigester consist of two
compartments namely;
fermentation chamber (digester)
and gas holder
• Make a hole in the middle of the
small drum.
•
Fix nozzle in the opening
•
Attach a rubber tube to the nozzle and close the free end of the
rubber tube.
•
Fill the larger container with about three quarters of the animal waste.
•
Place the open end of the shorter drum with the rubber tube in the
larger one.
•
Allow fermentation to take place in the digester for about two weeks.
•
Connect the free end of the tube to a Bunsen burner and light it.
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SUMMARY
➢ Non-renewable sources of energy cannot be replenished within a short
period of time.
➢ Fossil fuels are formed from buried remains of plants and animals that
died millions of year ago.
➢ Examples of fossil fuels are: petroleum, coal and natural gas.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. Which of the following is a renewable source of energy?
A. wind
B. petroleum
C. uranium
D. natural gas
2. All the following are sources of energy except?
A. coal
B. sand
C. wind
D. water
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3. Energy in the wind can be harnessed using ……….
A. solar panels
B. photovoltaic cells
C. windmills
D. nuclear plant
4. Biomass is an organic material made from plants and animals, which of the
following is a product of biomass?
A. biogas
B. petrol
C. diesel
D. liquid natural gas
5. Which of the following is a fossil fuel?
A. biodiesel
B. biogas
C. ethanol
D. crude oil
6. After drilling crude oil, it is refined through a process known as…………….
A. distillation
B. filtration
C. fractional distillation
D. segmentation
7. Animal waste and human sewage are converted into biogas in a process
called……………….
A. boiling
B. fermentation
C. fractional distillation
D. none of them
8. I come from dead plants and animals remains. I am deposited on the
ocean floor and sometimes on land. Am the greatest source of energy for
humankind. Who am I?
A. biomass
B. fossil fuel
B. biodiesel
D. biogas
9. Dams provide hydroelectricity using……………….
A. human waste
B. water
C. crude oil
D. natural gas
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10. Which of the following source of energy takes a longer period of time to
be replenished?
A. water
B. wind
C. crude oil
D. sun
UNIT 2: CONVERSION AND CONSERVATION OF ENERGY
LESSON 1: By the end of the lesson, student will be able to;
o State the law of conservation of energy
o List the various forms of energy
o Explain potential energy
o Explain kinetic energy
An energy conversion or transformation is the change of energy from one
form to another.
The law of conservation of energy states that energy cannot be created or
destroyed, but can be changed or transformed from one form into another.
Energy exist in different forms in the universe and they do different things.
1.1 FORMS OF ENERGY INCLUDE:
Potential energy, kinetic energy, heat energy, light energy, sound energy,
magnetic energy, sound energy, nuclear energy, chemical energy.
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1.2 POTENTIAL ENERGY
This is the energy which a body has by
virtue of position. It is a scalar quantity.
This form of energy is stored and waiting to
be used. For examples;
When we put a stone in the sling of a
catapult and stretch its rubber, potential
energy stored in it. This energy can throw
away the stone. Similarly, the water stores in the dam has potential energy. A
book sitting on your table and a mango hanging on a tree have potential
energy.
There are forms of potential energy:
Chemical potential energy: Anything that can be burnt or undergo chemical
reaction has chemical energy. It is stored in food, batteries and fuels such as
coal, petrol and natural gas.
Food, fuels and batteries release chemical energy as result of chemical
reactions.
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Gravitational potential energy
Gravitational energy is energy stored in
an object due to its height or elevated
position. When we raise a brick up to
some height, it possesses gravitational
energy.
Elastic potential energy: This is the energy stored in
elastic materials. This means the materials can be
stretched and compressed. Example is the energy
stored in a spring or catapult.
Finding the potential energy of a body
Potential energy (P.E) = mass (m) × acceleration due to gravity(g) × height(h)
P.E = m ×g ×h
Worked example
A body of mass 50kg was placed on a table of height 3m above the ground.
Find the potential energy of the body (take g= 10m/s2)
Solution
Potential energy = mass (m) × acceleration due to gravity(g) × height(h)
m = 50kg
g= 10m/s2
h= 3m
P. E= 50kg×3m×10m/s2
= 1500J
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1.3 KINETIC ENERGY
This the energy possessed by a body by virtue of motion/movement. This
means that any body or object of mass has kinetic energy. The faster the
motion of a body or object that higher its kinetic energy. For example, when
you are walking to school, your body possesses kinetic energy. A moving
water has kinetic energy.
Kinetic energy of an object depends on its mass and velocity.
𝟏
Kinetic energy =
𝟐
𝒎𝒗2
Where m is the mass of a body and v is its velocity.
Worked example
A car of mass 200kg is moving at a velocity of 4m/s. Calculate the kinetic
energy of the car.
Solution
Kinetic energy =
𝟏
𝟐
𝒎𝒗2
Mass (m) = 200kg, velocity (V)= 4m/s
Kinetic energy
1
=2×200×42
1600J
QUESTIONS:
1. In your own words define energy.
2. What is the unit of energy?
3. List four forms of energy.
SUMMARY
➢ Energy neither be created nor destroyed, but can be transformed from
one form to another
➢ The expression of potential energy is mass (m) × acceleration due to
gravity(g) × height(h)
➢ The expression of kinetic energy is 1/2 mv2
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LESSON 2: By the end of the lesson, student will be;
o Briefly explain the following; electrical energy, sound energy,
heat/thermal energy and light energy.
o Give examples of devices and processes in everyday life which use
energy and describe the change in the form of energy.
1.1 ELECTRICAL ENERGY
This is a form of energy that is produced as a result of moving electrons
through conductors. For example, torchlight produces electricity by
converting chemical energy in the dry cell to electricity. Other electrical
energy is obtained from solar cells, dynamos, dams etc. Electrical energy
lights our homes, run motors, and makers our TVs and radios work.
1.2 SOUND ENERGY
This energy is produced when an object is
made to vibrate. Sound energy travels out
as waves in all directions. Sound needs a
medium to travel through, such as air, water
and any solid material. Sound energy from
vibrating objects is carried by air to the ear.
Examples: Voices, whistles, horns and
musical instruments
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1.3 LIGHT ENERGY.
This a form energy that stimulates vision. It is made of electro-magnetic
radiation. Light moves in waves. The sources of light energy could be artificial
(man-made) or natural. Artificial sources of light include; torches, lamps,
candles etc. Natural sources are; sun, fireflies, deep sea fishes, glow worms
etc.
1.4 HEAT ENERGY /THERMAL ENERGY
This is the energy an object possesses as a result of movement of particles or
molecules within the object. The faster movement of molecules, the higher
the temperature. Heat energy flows from a warmer or higher temperature to
a cold or lower temperature until both reach the same temperature. Heat
energy is transferred from one
place to another because of
temperature difference. There
are three mode of heat
transfer; conduction in solids,
convection in liquids and
radiation in vacuum.
1.5 ENERGY TRANSFORMATION
Energy transformation is the changed of energy from one form to another.
Energy transformation occurs every day in our lives. For example, when you
put your television on, the tv convert electrical energy to light energy (for you
to see) and sound energy (for you to hear). Also, when you speak into your
phone, the phone convert sound energy to electrical energy. Electrical
energy is then converted to sound energy for the receiver to hear.
This confirms the law of conservation of energy.
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Activity
Demonstrating energy transformation
a) Work in a group
b) Materials needed: electric iron, public address system, calcium carbide
or sodium hydroxide, water, torch, batteries and source of power.
c) Plug the electric iron in a socket. Switch the socket on and observe the
metal plate after some minutes
d) Put the batteries in the torch and switch it on. Observe what happens
to the bulb.
e) Pour water into the beaker. Put calcium carbide in the water and
observe what happens.
f)
Put battery or plug-in the public address system. Speak through
microphone.
g) Discuss the energy transformation in each of the activity.
QUESTIONS
1. What energy changes takes place in each of the following processes?
a) When a mango drops from a tree
b) A carpenter hits a nail with a hammer.
c) A torch is switched on.
2. A boy throws a stone vertically up into the air. What are the energy
changes that take place as the stone falls to the ground?
ENERGY CONSERVATION
Most of our energy sources used in our homes and industries are nonrenewable. Therefore, there must be a sustainable use of energy as our
population increases because increased in population brings about high
demand for energy, increased in price of energy and tariffs on water and
electricity. We can have continuous energy supply by conserving it. The
following are some of the way we can conserve energy or avoid wastage of
energy.
✓ Switch off electrical appliance that are not in use, e.g. tv, radio,
electric iron, fans, computers etc.
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✓ Iron your dresses in bulk.
✓ Use energy efficient appliances.
✓ Install programmable thermostats to automatically turn off or reduce
heating and cooling when you are away or asleep.
✓ Close all windows and doors when using air conditioner.
✓ Do not leave your fridge opened for a very long time.
✓ Regularly maintain and repair all faulty electrical appliance.
QUESTIONS
1. Give three effects of increased in human population on the demand
for energy.
2. What is energy transformation.
SUMMARY
➢ Other forms of energy are; electrical energy, sound energy and heat
energy.
➢ Heat energy can be transferred by conduction, convection and
radiation.
END OF UNIT QUESTION
OBJECTIVE TEST
1.Which of the following energy changes takes place when a church bell is
tolled?
A. potential energy to kinetic energy
B. kinetic energy to sound energy
C. potential energy to sound energy
D. chemical energy to heat energy
2. A torch light bulb lights up when connected to a dry cell. What type of
energy is obtained from the dry cell?
A. light energy
B. potential energy
C. chemical energy
D. electrical energy
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3. Which of the following is the energy possessed by an object placed on top
of a table?
A. kinetic energy
B. potential energy
C. heat energy
D. sound energy
4. A dam for generating power is constructed across a river. What type of
energy is possessed by the water behind the dam?
A. kinetic energy
B. potential energy
C. electrical energy
D. light energy
5. A car battery produces electrical energy from…………………...
A. kinetic energy
B. heat energy
C. chemical
D. potential energy
6. The heat we eat undergoes slow oxidation in our bodies to produce heat.
In this process
A. chemical energy is converted to heat energy
B. electrical energy is converted to heat energy
C. kinetic energy is converted to heat energy
D. potential energy to heat energy
7. The energy that causes the turbine of hydro-electric plant to rotate is…
A. chemical energy
B. potential energy
C. electrical energy
D. kinetic energy
8.The energy stored in food is ………………………….
A. chemical energy
B. solar energy
C. thermal energy
D. kinetic energy
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UNIT 3: LIGHT ENERGY
LESSON 1: By the end of the lesson, student will be able to;
o Define light energy
o Give at least four sources of light energy
o Explain luminous and non-luminous bodies
o Explain the following terms: opaque object, translucent object and
transparent objects
o Give at least four characteristics of light
1.1 DEFINITION OF LIGHT ENERGY
Light energy is a form of electromagnetic radiation that can be seen by the
human eye. Light travels in the form of waves. The sun emits a large amount
of electromagnetic radiation. Humans are able to see only a fraction of this
energy which is known as ‘visible light’.
There are two main sources of energy namely;
✓ Natural sources of light which include the sun, stars, firefly, glow worms
etc.
✓ Artificial sources of light which include the lamps, lantern, torchlight
etc.
However, light can be emitted from luminous and non-luminous bodies.
Luminous bodies produce light on their own. Examples are; sun, candle, stars,
torchlights, bulbs, fire etc.
Bodies which do not produce or emit light on their own but reflect light that
falls on them from luminous bodies. These bodies are called non-luminous
bodies. Examples are; moon, water, mirror, glass, trees, sky etc.
Non luminous bodies or objects may be transparent, translucent and
opaque.
Transparent objects allow all the light to pass through them, translucent ones
allow partial light to pass, whereas opaque ones allow no light to pass
through
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1.2 CHARACTERISTICS OF LIGHT
✓ It is an electromagnetic wave.
✓ Light has different wavelength
✓ Light travels on a straight line
✓ Light travels with the speed of 3×108m/s in vacuum.
✓ Light can be reflected.
✓ Light can be refracted.
SUMMARY
➢ Light energy is an electromagnetic wave that stimulate vision.
➢ Luminous bodies produce light on their own but non-luminous reflect
light that falls on them.
➢ Non- luminous bodies can be transparent, translucent and opaque.
LESSON 2: By the end of the lesson, student will be able to;
o Demonstrate rectilinear propagation of light
o Use diagram to illustrate a ray and beam of light
o Define pin hole camera
o Give three characteristics of image formed on a pinhole camera
1.1 RECTILINEAR PROPAAGATION OF LIGHT
A light source can be seen only if there is straight line- path between the
source and your eyes. Therefore, rectilinear propagation of light means that
light travels on a straight line as a wave.
Activity: Demonstrating that light travels in a straight line.
a. Work in groups
b. Materials needed: three cardboard of the same size, candle, nail,
string and a ruler.
c. Set up the diagram below
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d. Observe the light at the other end of the set-up.
e. Discuss your findings.
f. Displace the middle cardboard slightly and observe the candle light
again.
g. Discuss your findings
QUESTIONS:
1. Explain your observation made when the three cardboards were in a
straight line.
2. What was observed when the middle cardboard was shifted slightly.
3. What conclusion can be drawn from the experiment?
4. With the aid of a diagram, describe an experiment to show that light
travels in a straight line.
Light travels in straight lines in rays. A ray is a path along which light travels in
a medium. It is represented by a straight line with an arrow mark on it showing
the direction in which the light is travelling.
a ray of light
Two or more light rays travelling together in the same direction form a beam.
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A beam of light may be parallel to each other spreading from a
point(diverging) or coming together at a point (converging)
The principle of rectilinear propagation of light is used to construct a pinhole
camera. A pinhole camera is the simplest camera that can be constructed in
our homes. The pinhole is simply an extremely small hole like you would make
with the tip of a pin in a piece of thick aluminium foil. It is the simplest
because the pinhole act as the lens.
It consists of a lightproof box, painted black on the inside to prevent multiple
reflection of light as light enters, a pinhole and a screen.
The image formed by the pinhole camera is;
✓ Real (can be seen on the screen)
✓ Diminished (smaller than the object)
✓ Inverted (turned upside down)
Project Work
a. Material needed: a shoe box, sticky tape, frosted glass, needle, some
tin of foil, scissors and a sharp knife.
b. Cut a square hole on the short side of the shoe box.
c. Tape the tin foil over the hole.
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d. Use the needle to make a hole at the centre of the tin foil.
e. Remove the cover of the shoe box
f. Place the frosted glass at end of shoe box opposite the pinhole to act
as the screen.
g. Cut another hole as the same side of the pinhole.
h. Make a shutter by placing a flap on the pinhole
i.
Point the camera towards a bright light.
j.
Observe the image formed on the screen.
k. What are the characteristics of the image formed on the screen?
l.
What happen if the pinhole is enlarged?
QUESTIONS:
1. Draw and label a diagram to show how an image is formed in a
pinhole camera
2. State three characteristics of the image formed on the screen of the
pinhole camera.
SUMMARY
➢ Rectilinear propagation of light means light travel in a straight line.
➢ Images formed in pinhole cameras are real, inverted and
diminished.
➢ Two or more rays are collectively called beam.
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LESSON 4: By the end of the lesson, student will be able to;
o Define the term shadow
o Demonstrate how shadow is form
o Identify the parts of a shadow
1.1 FORMATION OF SHADOWS.
A shadow is the area of darkness cast on a screen when an opaque object is
placed between a point source of light and the screen. A shadow is formed
when an object blocks the rays from the light source.
A cast shadow consists of two
parts: the umbra and the
penumbra. The umbra is
created because the direct
light has been completely
blocked and uniformly dark
shadow is formed (an opaque
object place between a point
source of light and a screen), while the penumbra is created by something
partly blocking the direct light (opaque object place between extended
light source e.g. incandescent bulb). Penumbra always surrounds the umbra.
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Activity. How shadow is formed
a. Work in group
b. Materials needed: a screen, incandescent bulb, torchlight and a ball.
c. Place the ball between the torchlight and the screen.
d. Switch on your torchlight.
e. Observe and identify the various parts
f. use the incandescent bulb instead of the torchlight and observe.
QUESTIONS:
1. Define the following
a. Shadow
b. Umbra
c. Penumbra
2. With the aid of a diagram describe how shadow is formed.
SUMMARY
➢ Shadow is the area of darkness cast on a screen when an opaque
object is placed between a source of light and the screen.
➢ A shadow has two parts; umbra and penumbra.
➢ Penumbra always surrounds umbra.
LESSON 5: By the end of the lesson, student will be able;
o Define the term eclipse
o State two types of eclipse
o Demonstrate how eclipse is formed
1.1 FORMATION OF ECLIPSE
It is the total or partial appearance of the sun or moon from the earth. An
eclipse takes place when one heavenly body such as a moon or planet
moves into the shadow of another heavenly body.
1.2 THERE ARE TWO TYPES OF ECLIPSE NAMELY;
✓ Solar eclipse
✓ Lunar eclipse
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Solar eclipse / eclipse of the sun.
Solar eclipse occurs during
the day when the moon
comes between the sun
and the earth in a straight
line. The moon casts a
shadow onto the surface of
the earth.
The shadow has umbra surrounded by penumbra. It occurs within a short
period of time. People in the umbra region cannot see the sun at all but
people in the penumbra region can partly see the sun.
Lunar eclipse/ eclipse of the moon.
This type of eclipse occurs in the night when earth is between the moon and
the sun in a straight line. The shadow of the earth is cast on the moon. The
phenomenon last for a long time.
QUESTIONS
1. What is meant by the term eclipse?
2. What is eclipse of the sun?
3. With the aid of a diagram, distinguish between total eclipse and partial
eclipse.
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SUMMARY
➢ Eclipse refers to the total or partial appearance of sun or moon the
earth.
➢ Eclipse of the sun occurs in the day when the moon comes between
the sun and the earth in a straight.
➢ Eclipse of the moon occurs in the night when the earth comes
between the sun and the moon in a straight line.
LESSON 6: By the end of the lesson, student will be able to;
o Define the term ‘reflection of light’
o Define the following term: incident ray, normal, reflected ray, angle of
incidence and angle of reflection.
o State the law of reflection
1.1 REFLECTION OF LIGHT
When a ray of light falls on a
polished and shining surface of
an object, it bounces back. The
process of sending back the
light rays after falling on the
shining surface of an object is
called reflection of light.
When light rays fall on an object, the rays are reflected. The reflected rays
reach our eyes and we are able to see the object.
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The ray of light which falls on the surface of mirror is called incident ray
The point at the
surface of mirror at
which the incident ray
falls is called the point
of incidence.
When the incident ray
falls on the surface of a
mirror, the mirror sends
it back in another
direction (in same medium). The ray of light which is sent back by the mirror is
called reflected ray.
Normal may be defined as a line which is perpendicular to the mirror at the
point of incidence.
The angle of incidence may be defined as the angle which is made by the
incident ray with normal at the point of incident. It is denoted by the letter θi.
The angle of reflection may be defined as the angle which is made by the
reflected ray with normal at the point of reflection. It is denoted by the letter
θr.
1.2 THE LAW OF REFLECTION STATES THAT
✓ The incident ray, the reflected ray and the normal, at the point of
incidence, all lie in the same plane.
✓ The angle of incidence is equal to angle of reflection. It means that
during the reflection of light if the angle of incidence is 150 then the
angle of reflection will also be 150. I.e. θi=θr
The law of reflection answers the question; why do we see ourselves in the
mirror or why you see your book sitting on the table. For example, you are
able to see your book sitting on the table because, light stroked on the book
and reflected directly to your eyes.
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SUMMARY
➢ Reflection of light is the bouncing back of light when it strikes on a
surface.
➢ It occurs in the same medium.
➢ The law of reflection states that; The incident ray, the reflected ray and
the normal, at the point of incidence, all lie in the same plane.
The angle of incidence is equal to angle of reflection.
LESSON 7: By the end of the lesson, student will be able to;
o State the two types of reflection
o Use diagram to illustrate the types of reflection
o Define virtual image
o Define real image
o Discuss the characteristics of image form on a plane mirror
o Give at least four application of plane mirror
1.1 TYPES OF REFLECTION
Base on the surfaces the light strikes, we
going to have types of reflection.
When light rays or beam of light strike
on a smooth surface like a mirror the
rays collectively reflect together with
the same intensity and undisturbed. This
type of reflection is called regular or
specular reflection.
Regular or specular reflection
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Also, when rays of light fall on a rough
surface like terrazzo wall, the rays reflect
with different intensity and direction. This
type of reflection is called irregular of
diffuse reflection.
Irregular or diffuse reflection
QUESTIONS:
1. Define the following terms
a) Incident ray
b) Reflected ray
c) Incident angle
d) Reflected angle
2. State the law of reflection.
3. A ray of light strikes the surface of a plane mirror at angle of 55 0. Draw
a ray diagram to show the normal, incident ray and the reflected ray.
What is the angle of reflection for the ray?
1.2 HOW AN IMAGE IS FORMED IN A PLANE MIRROR.
An image is produced at a point where two or more light rays from an object
meet or appear to meet. There are two types of images namely;
✓ Virtual /apparent image: this image is produced where light rays do not
actually intersect. Plane mirrors produce virtual images; the image is
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located behind the mirror where light does not actually come from.
Virtual images are not formed on the screen.
✓ Real image: this is an image formed by the actual intersection of light
rays. Real image can be formed on the screen. For example, images
captured by cameras are real images.
Activity: formation of image in a plane mirror
a. Work in groups
b. Material needed: plane mirror, measuring tape, pins
Image formed in a plane mirror is
✓ Virtual
✓ Erect i.e. upright
✓ Image is the same as object
✓ The distance of the object in front of the plane mirror is equal to the
distance from the plane mirror to the image.
✓ Laterally inverted (left side comes to the right and vice versa)
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1.3 APPLICATION OF PLANE MIRRORS
Dressing mirror
periscope
security mirror at supermarket
driving mirror
barbering shop
used in microscopes
to focus light onto
specimen
PROJECT WORK: use simple materials in your environment to construct a
periscope
SUMMARY
➢ Regular reflection occurs on a smooth surface but irregular reflection
occurs on a rough surface.
➢ Real image is formed on the screen.
➢ Virtual image cannot be formed on the screen.
➢ Images formed in the plane mirror are virtual.
LESSON 8: By the end of the lesson, student will be able;
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o define refraction of light
o demonstrate light changes path when it passes from one medium to
another.
o use ray diagram to illustrate refraction of light.
o State the law of refraction
1.1 REFRACTION
As we have learnt from the property of light, light can be refracted. When
light passes from air into another transparent object like water, the direction
of the light changes.
The change in direction of the light ray when it travels from one medium to
another medium of different optical density is called refraction of light. The
tendency of a ray of light to bend in one direction or another is dependent
upon whether the light wave speeds up or slows down upon crossing the
boundary.
The more optically dense that a material is, the slower that a wave will move
through the material. Materials with the same optical density will not show
any refraction when light cross the boundary.
When light travels from a less dense to an optically denser medium, the ray of
light bends towards the normal hence, the angle of incidence will be greater
than the angle of refraction and the vice versa.
QUESTION: Explain what will happen when light travels from an optically
denser medium to a less dense medium.
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Activity: refraction of light
a. Work in group
b. Materials needed: a beaker,
pencil, and water
c. Place the pencil in the beaker
and observe what happens.
d. Pour a suitable amount water
in the beaker.
e. Place the pencil in the beaker
containing the water and
f. observe the pencil.
g. Why did the pencil bend in the water?
The diagram below shows the refraction of light as it passes from one
substance (air) to another substance (water).
1.2 LAWS OF REFRACTION
The law of refraction is also known as Snell’s law. Snell’s law states that;
the incident and refracted ray are on opposite sides of the normal at
the point of incidence all lie in the same plane.
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✓ The ratio of the sine of the angle of incidence to the sine of the angle
of refraction is constant for a given pair of media.
This constant is the refractive index of second medium relative to the
first medium. This means that degree of refraction depends on the ratio
of the two material’s refractive indices.
QUESTIONS: Observe the figure below carefully
1. Find the point where the ray leaves the glass. Does it bend away from
the normal?
2. b Which way does the ray bend when it enters the glass?
SUMMARY
➢ Refraction of light is the change in the direction of light ray when it
travels from one medium to another medium of different optical
density.
➢ When light travels from air to water, it bends towards the normal and
the vice versa.
LESSON 9: By the end of the lesson, student will be able to;
o Explain why an object at the bottom of a pond appears closer to the
surface
o Give at least three applications of refraction in our everyday life
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Activity: finding real and apparent depth.
a.
Work in groups
b.
Materials needed: a beaker, water and
a coin
c.
Place the coin beaker and observer the
depth of the coin
d.
Pour water onto the coin in the beaker
and observe the position of the coin in the
beaker.
e.
Discuss your findings
QUESTIONS:
1) what is real depth
2) what is apparent depth.
3) Explain why a coin appears to be raised in a beaker containing water.
4) What would happen if light travels from a dense medium to an
optically denser medium? Illustrate with a diagram.
Refraction of light causes materials such as pens, pencils and sticks appear
bent when partially immersed in water.
Refraction of light causes
mirage. This occurs during
very hot weather. As light
travels from cooler region to
hotter region, refraction
occurs, which changes the
direction of the light and
reflect to our eyes as a
mirrored ground. In the
actual sense, we see the
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ground but since our mind understand that light travels in a straight line, we
see a mirrored or a pool of water ahead of us.
Refraction also causes object at the bottom of water appear to be raised.
Refraction also causes objects like lemon place in water appear bigger that
its original size when viewed from the side.
A pool of water appears less deep than
actual depth as a result of refraction.
APPLICATIONS OF REFRACTION IN OUR EVERYDAY LIFE.
✓ Cameras use lens to refract light and project image on a light sensitive
film so that image will be recorded.
Activity:
a) work in groups
b) materials needed: magnifying lens, candle, a screen (a sheet of
paper), a match and candle.
c) In a dark room, place your paper on a wall
d) light the candle
e) place the magnifying lens between the screen and candle.
f) Move the magnifying lens back and forth until a focused image of the
candle is formed on the screen.
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✓ Eye glasses and contact have lenses that are used to correct refractive
error in the eye.
When light rays from a distance are focused before it reaches the
retina, the image formed becomes blur causing near-sightedness or
short-sightedness. This defect can be corrected using a diverging lens
to refract the light so the that the image would be focused on the
retina.
If light is not focused by the time it gets to the retina i.e. focusing occurs
beyond the retina, the person cannot focus near object. This causes
far-sightedness or long sightedness. This defect can be corrected using
converging lens to refract and focus image on the retina for clear
vision.
✓ Some telescopes use the principle of refraction to view distant object.
✓ Dispersion of light: it is the separating or splitting of light into its
component when it passes through transparent object such as prism
and water. The component of light is; red(R), orange(O), yellow(Y),
green(G), blue(B), indigo(I), and violet(V) ROYGBIV. The bands of these
colours is called spectrum. Each of the colours has an of deviation.
When light passes through a transparent material each of the light
deviate through a certain angle.
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The formation of rainbow is based on the principle of dispersion of light.
QUESTIONS:
1) define the term dispersion of light?
2) draw and label a diagram of dispersion of light through a triangular
prism.
3) briefly describe how rainbow is formed.
The colours that cannot be obtained by mixing any other colours in any
proportions are called primary colours. The primary colours of light are red,
green, and blue.
The colours produced by mixing
any two primary colours of light
are called secondary colours or
composite colours. Magenta,
cyan and yellow colours are
secondary colours.
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SUMMARY
➢ Refraction of light causes a coin in water higher in water.
➢ The splitting of light into it various component when it pass through
transparent object referred as dispersion of light.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. The path along which light travels is known as…...
A. Light ray
B. electromagnetic wave
C. wave
D. direction of incidence
2. Which of the following is a man- made source of light
A. torchlight
B. moon
C. sun
D. glow worm
3. The darkest part of a shadow formed when during an eclipse is called…
A. umbra
B. penumbra
C. eclipse of the sun
D. eclipse of the moon
4. What happens when light rays from the sun fall on a mirror
A. it is absorbed
B. it is reflected
B. it is diffracted
D. it refracted
5. Which of the following sources of light is natural source of light
A. firefly
B. torchlight
C. lantern
D. light bulb
6. Formation of shadows work on the principle of ………...
A. refraction of light
B. diffraction of light
C. light travels in a straight-line
D. reflection of light
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7. Which of the following is not a characteristic of image formed on a pinhole
camera?
A. it is diminished
B. it is inverted
C. it is real
D. it cannot be formed on a screen.
8. When light travels from air to water, it will…………….
A. bend away from the normal
C. bend into the normal
B. bend towards the normal
C. bend perpendicular to the normal
9. Which of the following statements describes transparent bodies?
A. it allows part of light to pass through
B. it blocks all light rays
B. it allows all light to pass through
D. it reflects light
10. The change in direction of light as it travels from air to water is
called………
A. deflection of light
B. refraction of light
C. reflection of light
D. absorption of light
11. The splitting of light into it component as it passes through a transparent
prims is called………..
A. direction of light
B. deflection of light
C. dispersion of light
D. reflection of light
12. A region where no light falls is called…………………..
A. shadow
B. image
C. light path
D. object
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UNIT 4: BASIC ELECTRONICS
LESSON 1: By the end of the lesson, student will be able to;
o Explain the term electronics.
o List four components of electronic circuit
o Define semi-conductor
o Define doping
o Give the difference between N-type and P-type semiconductors
1.1 EXPLANATION OF ELECTRONICS
Electronics is a branch of physics that deals with the study of flow and control
of electrons. The control of flow electrons is accomplished by devices that
resist, carry, switch, manipulate and store.
It deals with electrical circuit and their various components such as, diodes,
resistors, capacitors, inductors, transformers, light emitting diodes and P-N
junction diode
The battery produces the voltage and current that drives or powers the
electronic components. All electronics equipment works on a fundamental
physics principle known as Ohm’s law, which states that a circuit contains a
voltage directly proportional to the current and resistance
1.2 SEMICONDUCTORS
Semiconductors and semiconductor technology form the basis of most of the
electronics industry these days. Transistors, diodes, integrated circuits and
many more devices all have semiconductor technology in common.
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Semiconductors are materials whose conductivity lie between conductors
and insulators. They are not good conductors nor good insulators. Examples
of such materials are silicon, germanium, gallium arsenide and others.
Semiconductor’s conductivity can be controlled.
Silicon
QUESTIONS
1. What is electronics
2. State four components of electronic circuit
1.3 DOPING
Semiconductors cannot conduct electricity at low temperature. This is
because the electrons of semiconductors are not able to free themselves to
move and conduct electricity.
They can conduct electricity very well at higher temperature and adding
impurities. These impurities are called donors or acceptors.
The process of adding donor or acceptor atoms to semiconductor atoms is
called doping.
Doping a silicon material with sufficient numbers of impurities, we can turn it
into either an N-type or a P-type semiconductor material.
But simply connecting a silicon crystal to a battery supply is not enough to
extract an electric current from it. To do that we need to create a “positive”
and a “negative” pole within the silicon allowing electrons and therefore
electric current to flow out of the silicon.
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A semiconductor with excess carrying electrons, which is negative charge is
called N-type semiconductor.
In the same way a semiconductor with excess positive charge carriers is
called P-type semiconductor.
QUESTIONS
1. What are semiconductors?
2. Give three examples of semiconductors
3. Give three devices made from semiconductors
4. What is doping?
5. What is the difference between N-type and P-type semiconductors?
SUMMARY
➢ Electronics is a branch of physics that deals with the study of flow and
control of electrons.
➢ The various components of electronic are; diodes, resistors, capacitors,
inductors, transformers, light emitting diodes and P-N junction diode.
➢ The process of adding donor or acceptor atoms to semiconductor
atoms is called doping.
➢ A semiconductor with excess negative charge carriers is called N-type
semiconductor.
➢ A semiconductor with excess positive charge carriers is called P-type
semiconductor.
LESSON 2: By the end of the lesson, student will be able to;
o define p-n junction diode
o explain the term biasing
o give at least four applications of p-n junction diode
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1.1 DIODE
A P-N junction is formed when an N-type material is fused together with a Ptype material creating a semiconductor diode.
When N-type material is fused with P-type material, electron and holes move
back and forth until a potential barrier is formed. When we make a
connection to the ends of both N-type and P-type material and then
connect to a battery source, the potential barrier is broken and electrons are
made to flow. The result is that PN junction diode is produce.
A diode is an electronic device that allows a free flow of electrons in only one
direction.
1.2 BIASING
The process of applying voltage to P-N junction diode to conduct is called
biasing.
A diode has a positive and negative terminal.
Current flows from the anode to the cathode.
There are two ways of biasing namely; forward and reverse bias. a diode is
said to be zero biased when it not connected to any external energy source.
When the P-type region is connected to the positive terminal of the battery
and the N-type region is connected to the negative terminal of the battery it
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is called forward biasing. Forward bias allows current to flow fully because
depletion layer is reduced.
Also, when the P-type region is connected to the negative terminal of the
battery and the N-type is connected to the positive terminal of the battery, it
is called reverse biasing. Resistance is higher, depletion is larger hence little or
no current flow.
1.3 APPLICATION OF DIODE
⚫
It is use to prevent current from flowing to unintended direction.
⚫
It is used to detect radio signals
⚫
It can be used as temperature measuring device.
⚫
It is used as over-voltage protector
⚫
Diodes are used to construct rectifiers which are used in automotive
alternators.
⚫
Used in the generation and detection of light
SUMMARY
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➢ A diode is an electronic device that allows a free flow of electrons in
only one direction.
➢ When the P-type region is connected to the positive terminal of the
battery and the N-type region is connected to the negative terminal of
the battery it is called forward biasing and the opposite is called
reverse biasing
➢ Forward bias allows current to flow fully.
➢ Resistance is higher in reverse bias
LESSON 2: By the end of the lesson, student will be able to;
o Define the term Light Emitting Diode
o Draw the symbol of LED
o Demonstrate the behaviour of LED in a circuit
o Give at least four application of LED
1.2 LIGHT EMITTING DIODE (LED)
Light emitting diode is a specialised semiconductor device that converts
electrical energy to light energy.
When a diode is forward biased, electrons are released that produce
sufficient energy to produce photon which emit a single coloured light
(monochromatic light). This means that an LED will pass current in its forward
direction but block the flow of current in the reverse direction.
LED
Symbol
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Activity: forward and reverse biasing
a) Work in groups
b) Materials needed: p-n junction diode, LED, 3V battery, key or switch, and
connecting wire.
c) Construct an electronic circuit with the LED in series.
d) Close the key and observe what happens.
e) Open the key and observe what happens to the LED
f)
Add a P-N junction diode to the circuit.
g) Close the circuit and observe what happen to the LED
h) Open the circuit and observe what happens to the LED.
1.2 APPLICATIONS OF LED
⚫
It is used as flashlight in our homes.
⚫
Led is used in dimming of light
⚫
It is used for smartphone backlighting
⚫
It is used as On-Off indicators in various electronic circuit
⚫
LED is used in signalling light such as traffic light
QUESTIONS
1) What is diode?
2) Indicate the circuit symbol for p-n junction diode
3) Explain the term biasing
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4) Define the following terms
i.
Zero biasing
ii.
Forward biasing
iii. Reverse biasing
1) What will happen if the P-type region of diode is connected to the
positive terminal of a battery.
2) How do reduce the flow of current in biasing?
SUMMARY
➢ Light Emitting Diode is an electronic device that convert electrical
energy to light energy.
➢ It is used as flashlight in our homes.
LESSON 3: By the end of the lesson, student will be able;
o Define a resistor
o Draw the symbol of a resistor
o Examine colour code resistor
o Demonstrate the behaviour a resistor in a circuit
o Give at least three application of resistors
1.1 RESISTOR:
A resistor is an electronic device that opposes the flow of current or is used to
control the flow of current in an electronic circuit. Resistance is measured in
ohms(Ώ).
An ohm is the resistance that occurs when a current of one ampere
passes through a resistor with a one volt drop across its terminals.
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resistor
symbol
Resistors that have variable resistance are called variable resistors. An
example of variable resistor is rheostat.
Variable resistor or rheostat
symbol
In electronics, the value of a resistor is indicated by colour band. In most
resistors, there are four colour bands. The value determines how strongly the
resistor oppose the flow of current.
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Activity; investigating the action of resistors
a) Work in groups
b) Materials needed: 3v battery, LED, different resistors with different
resistance (300 and 3,300Ώ) and connecting wire.
c) Construct a circuit with LED and resistor with resistance 300 Ώ in series.
d) Close the key and observe what happens to the LED
e) Use replace the 300Ώ with the 3,300Ώ resistor
f)
Observe what happens to the LED and record your observation
1.2 USES OF RESISTORS.
⚫
Control the flow current in electronic circuit
⚫
It is used to divide voltage.
⚫
It is used in heat generation. For example, it is used in kettles to convert
electrical energy to heat energy.
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QUESTIONS
1. What is a resistor?
2. Indicate the circuit symbol of a resistor.
3. Draw an electronic circuit diagram with a resistor and explain the
importance of the resistor in your circuit.
SUMMARY
➢ A resistor is an electronic device that opposes the flow of current in an
electronic circuit.
➢ A resistor with variable resistance is called rheostat.
➢ Resistance is measured in ohms
LESSON 4: By the end of the lesson, student will be able to;
o Define capacitor
o Draw the symbol of a capacitor
o Demonstrate charging and discharging action of capacitors
1.1 CAPACITORS:
Capacitor is an electronic component with two terminals that has the ability
to store electrical energy and release it when needed.
Parallel plate capacitor consists of two metal plates separated by a layer of
insulating material called dielectric. It is measured in farad (F). Most of the
capacitor have very small capacitance, so they are measured in
microfarads (µF). The higher the capacitance, the more energy it can store
for a given voltage.
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Symbol
The name of a capacitor depends on the type of dielectric used in
construction. Examples: ceramics, mica, plastic, electrolyte etc. Capacitors
may also come in different shapes and sizes.
Different types of capacitors
1.2 HOW CAPACITOR WORKS
A capacitor has two plates. If we connect a battery to the plates, electrons
flow from the plate connected to the positive terminal of the battery to the
plate connected the negative terminal of the battery.
Electrons won’t be able to pass through the capacitor because of the
dielelectric material, so they start accumulating on the plate. As more and
more electrons accumulate, the battery will have insufficient energy to push
any new electrons to enter the plate because of the repulsion of the existing
electrons, consequently, the plate becomes negatively charged and the
other plate become positively charged, then electric field build up.
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Once the capacitor is fully charged, if we remove the battery, the capacitor
will still hold the electric charge, acting as a storage.
When we connect a lamp to the capacitor, current will start flowing through
the lamp and it will light up. The accumulated electrons from the first plate
will start moving to the second plate, until both plates become back again
electrically neutral. This process is called discharging.
Activity: investigating charging and discharging of capacitor
a) Work in groups
b) Material needed: 9V battery, 100µF capacitor, connecting wire, resistors
and a LED
c) Connect the circuit according to the schematic diagram below
d. Open the circuit and observe what happens to the LED.
e. Explain charging and discharging action of capacitors.
If you have used a digital camera before, there is a capacitor attached to
the flash light that charges up after you have pressed the snap button. Once
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that capacitor is fully charged by the camera’s battery, all of that energy
explodes outward in a blinding flash of light.
Touch screen mobile phone and tablets make use of capacitive touch
screens.
These glass screens have a very thin, transparent metallic coating. There is a
built-in electrode pattern that charges the screen so when touched, a
current is drawn to the finger and creates a voltage drop. This exact location
of the voltage drop is picked up by a controller and transmitted to a
processor.
QUESTIONS
1.
Define the following terms;
A. Capacitor
B. Capacitance
C. Charging in capacitors
2.
Draw a circuit symbol for capacitor
3.
How would you discharge a capacitor?
4. Use a diagram to show how capacitor is charged.
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SUMMARY
➢ Capacitor is an electronic device that store charges.
➢ The capacitance is measured in farads.
➢ It is used in cameras.
END OF UNIT QUESTIONS
OBJECTIVE TEST
1. Which of the following electronic component will you use when your
constructing an electric heater?
A.
p-n diode
B. integrated circuit
C. variable resistor
C. a lamp
2. Which of the following statement best describe a diode
A. it allows current to flow in different direction.
B. it allows current to flow in all direction.
C. it allows current to flow in one direction.
D. it stores electric charges
3. The process of adding impurities to semiconductor atoms is called
A. doping
B. adding
C. injection
D. charging
4. A material whose conductivity lies between a conductor and insulator is
called…...
A. resistor
C. capacitor
B. semiconductor
D. diode
5. An insulating material that separates the two-metal plates in a capacitor
is called……
A. nonelectric
B. dielectric
C. semiconductor
D. electric
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6. A current flow in a diode when it is …….
A. forward biased
B. reverse biased
B. backward biased
D. doped
7. Which of the following statement about resistance is true?
A. as resistance increases, more current flows
B. as resistance increases, less current flows
C. as resistance increase, more energy is produced
D. as resistance increase, no heat is produced
8. A diode is said to be forward biased when………
A. the P-region of the diode is connected to the positive terminal of
the battery and the N-region to the negative terminal
B. the P-region of the diode is connected to the negative terminal of
the battery and the N-region to the positive terminal.
C. both the P-region and N-region is connected to positive terminal of
the battery.
D. only the P-region is connected to the negative terminal of the
battery
9. The process of applying voltage to a P-N junction diode is called……….
A. reversing
B. biasing
C. doping
D. charging
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SECTION 6: INTERACTIONS OF MATTER
General Objectives:
✓ appreciate that interactions between and within matter helps humans to
better understand the environment and their role in it.
✓
show understanding of ecosystems.
✓
trace the interdependency of organisms in an ecosystem.
✓ develop skills of managing waste in the environment.
✓
show understanding of both physical chemical processes in everyday life
✓ appreciate that air is an important type of matter that can be polluted as
some result human activities.
UNIT 1: ECOSYSTEM
LESSON 1: By the end of the lesson, student will be able;
o define the term ‘ecosystem’
o explain the following terms; producers, consumers and decomposers
o define the term habitat.
o Define the following term: population, community and species.
o Define adaptation
1.1 DEFINITION OF ECOSYSTEM
The environment is made up living and non-living things. Living things and
non-living things co-exist in the environment. The scientific study of living
things and their interrelationship within the environment is called ecology.
Therefore, an ecosystem can be defined as a biological unit that consist of
both living things and non-living things interacting with each other. An
ecosystem must be self-supporting or balanced.
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1.2 DEFINITION OF TERMS IN ECOSYSTEM
For an ecosystem to be self-supporting, it must contain the following
components;
✓ Producers: organisms that able to make their own food using the
energy from the sun i.e. photosynthetic organisms
✓ Consumers: organism that depend on others for food
✓ Decomposers: organisms that break down dead and decomposing
organic matter.
Non-things include; air, water, soil, temperature, humidity etc.
All living things in an ecosystem are interdependent and there exist variation
among all of them.
QUESTION
What will happen to an ecosystem if it is not balanced or self-supporting?
An ecosystem can be small such, e.g. a pond or large, e.g. forest. An
ecosystem is made of a number of habitats and communities.
✓ Habitat: a habitat is a place where an organism can live and
interbreed successfully. For example, the habitat for tilapia is
freshwater. This is because tilapia has certain structures that enable it to
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live successfully and reproduce. Tilapia cannot live successfully on
land because, that is not its habitat.
Freshwater habitat
Basically, there are two types habitat namely;
Terrestrial habitat which include forest, grassland, wetland and desert.
Forestland
desert land
Aquatic habitat includes marine and freshwater habitat.
Marine habitat is salty and it include the seas and oceans. Octopus, shrimps,
herring, tuna, crabs are some organisms that can be found in marine habitat.
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Freshwater habitat has no salt. Examples of fresh water are lakes, streams,
pond and rivers. Tilapia, catfish and other living organisms are found in
freshwater habitat.
✓ Community: it refers to all the living organisms living in a habitat. A
community is made of a number of different species.
✓ A species is a group of organisms that can interbreed and produce
fertile offspring. For example, a group of goats form a species and a
group of sheep form a species. Although they are closely related, they
belong to different species.
✓ The total number of organisms of the same species living in a habitat is
referred as population.
1.3 ADAPTATION
All living organisms in the environment should be able live and reproduce
successfully but they are affected by the conditions of their habitat. These
conditions or factors determine the type of living organisms that are able to
inhabit that area. These factors are abiotic factors (light, soil, humidity,
temperature, water, wind) and biotic factors (competitors, parasites,
predators etc.). Therefore, living things must adjust to the conditions imposed
on them by their environment.
Moth adapting to prevent
predators.
Green tree python adapted to
live on branches
Living organisms may change their behaviour i.e the way the respond to the
environment. They may also change their physiology i.e. their body processes
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and also their structure i.e. features that will enable them to survive and
reproduce successfully.
Chameleon camouflaging
plant adapted to eat insects
Adaptation can be defined as behavioural, structural or physiological
characteristic that has develop to help an organism to live successfully in its
environment.
Living organisms can protect themselves from predators and adapt to new
environments through adaptations. Adaptation brings about diversity of living
things.
QUESTIONS:
1. Explain the term ecosystem.
2. Define the following terms:
a. Habitat
b. Community
c. Population
d. Species e. Adaptation
SUMMARY
➢ An ecosystem consists of living and non-living things interacting with
each other.
➢ Habitat is a place where an organism can live and interbreed
successfully.
➢ Living things have features that enable them to live successfully in their
environment.
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LESSON 2: By the end of the lesson, student will be able to;
o Describe how tilapia is adapted to its environment.
o Give reasons why a fish from the sea may not survive in a fresh water
environment.
o Describe how weaver bird is adapted to its environment.
1.1 ADAPTATION OF TILAPIA TO LIVE IN FRESHWATER HABITAT.
Tilapia has several features that help it live successfully and reproduce.
✓
it has streamlined body shape that enable it to move quickly and
smoothly in water.
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✓
The presence of lateral line helps the fish to detect vibration in water
caused by pressure to escape predators.
✓
The scales protect the fish and help the fish to swim smoothly.
✓
The pectoral and pelvic fins allow the fish to steer, balance and brake
when swimming.
✓
The caudal fin helps to propel the fish forward.
✓
The dorsal fin helps in yawing and rolling.
✓
It has an operculum to protect the gills from damage
✓
The gills are highly vascularised to enhance exchange of gases.
REASONS WHY A FISH FROM THE SEA MAY NOT SURVIVE IN A FRESH WATER
ENVIRONMENT.
Fish from the sea water has body with body fluids same as the concentration
of the sea water (isotonic). If you put a sea fish in freshwater, because the
body fluids of the sea fish are of higher concentration (hypertonic) as
compared to the freshwater, freshwater will move into the fish by osmosis. The
cells of the sea fish will be filled with water and finally burst, resulting in the
death of the fish.
QUESTIONS:
1. Make a well labelled diagram of tilapia.
2. Explain four features of tilapia that enable it to survive and reproduce
successfully in its environment.
3.
Freshwater fish may not survive in sea water. Give reasons for this
phenomenon
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Adaptations of weaver bird to its environment
They nest in colonies, and are very noisy with a lot of activities in the area
they have their nests.
✓ The body is covered with feathers for insulation against excessive cold.
✓ It has light and hollow bones to reduce weight to enable it to fly.
✓ Forelimbs are modified into wings, which are used for flight.
✓ The presence of tail feathers in weaver bird help in steering and
balancing during flying.
✓ The streamlined body shape helps the bird to fly through the air with little
resistance.
✓ Its mouth is modified into a beak for eating and making nest.
✓
the weaver bird has lungs which aid in gaseous exchange.
✓
The breastbone is modified into a keel bone for attachment of flight
muscles.
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SUMMARY
➢ Tilapia has fins, lateral line and gills that enable it to survive in its habitat
➢ Adaptation explains why a fish from the sea may not survive in a fresh
water.
➢ Weaver bird has feather, streamlined body and modified mouth that
enable it to live successfully.
LESSON 2: By the end of the lesson, student will be able to;
o Describe how cactus plants are adapted to their environment.
o Outline some adapted features of predators and preys.
1.1 ADAPTATION OF CACTUS PLANTS
Different types of cactus plants
Cactus plants live in desert environment and sandy coastal belt where water
is scarce. To adjust to this condition, cactus plants have adapted to allow it
live successfully in the desert and sandy coastal belt. Cactus plants have the
following adaptation;
✓ Their leaves are modified into spine to minimize surface to reduce the rate
of water loss during transpiration.
✓ The spines also protect them from animals that might eat them.
✓ They have modified thick fleshy stems that can store large amount of
water during drought season.
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Its fibrous roots are spread out to collect water when it does rain and it
✓
stores water in its body for future use.
✓ The thick green fleshy stems are modified and used for photosynthesis.
1.2 SOME ADAPTIVE OF FEATURES OF PREDATORS AND PREY
Apart from the adaptations of the living organisms discuss above, organisms
that hunt, kill and eat other organisms (predators) have certain features that
enable to survive successfully. Some of the adaptation of these organisms
are;
✓ Some animals like eagles, lions and snake have sharp eyes that enable to
hunt for other animals far from them.
✓ Carnivorous animals have modified long canine and carnassial teeth to
enable them to hold and tear flesh.
✓ Others like frogs and toads have long sticky tongue to catch prey.
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✓ Some animals like eagles and hawks have long and strong sharp claws to
enable them catch their prey.
✓ Some have modified eye to see in the night.
Organisms that are fed upon are able survive in their environment by
Camouflaging, mimicry, secretion poisonous substance and spines on their
body serves as defensive mechanism.
QUESTION:
State and explain three ways by which plants protects themselves from
danger
SUMMARY
➢ Cactus plant lives an environment where water is scarce.
➢ It is a modified leaves, stem and root to enable it live successfully in the
desert.
LESSON 3: By the end of the lesson, student will able to;
o Explain the term food chain
o Define the following term: primary consumers, secondary consumers
and tertiary consumers.
o Use a diagram to illustrate food chain.
o Define food web
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INTRODUCTION
Where do we get energy from? Our energy comes from the food that we
eat. The major source of energy in our planet is the sun. Green plants use the
energy from the sun to make food in a process known as photosynthesis.
In an ecosystem, living things are able to maintain themselves by cycling the
energy they have obtained. How living organisms obtain the energy and
transfer it to another is through food web and its constituent food chain.
1.1 WHAT IS FOOD CHAIN?
Food chain is a linear feeding relationship among living organisms in which
energy is transferred from organism to another.
In food chain, there are feeding levels (trophic levels) which show the parts
and path of energy transfer among living things.
⚫
The first trophic level or part of the food chain is the primary producers.
The primary producers use solar energy to produce organic material
through photosynthesis. They form the base of food chain. These are
autotrophs because they produce food own their own and such
organisms include plants and algae.
⚫
Consumers occupy the second tropic level. There are different types of
consumer in the food chain;
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✓
The organisms that eat the primary
producers are called primary consumers.
Primary consumers are usually herbivores, planteaters, though they may be algae eaters or
bacteria eaters. Examples: sheep, goat, cattle,
giraffe etc.
Giraffe feeding on producer(plant)
✓
The organisms that eat the primary
consumers are called secondary consumers.
Secondary consumers are generally meat /flesh
eaters—carnivores. Examples; snakes, dogs,
insectivorous plants etc.
Dog feeding primary consumer
✓
The organisms that eat the secondary
consumers are called tertiary consumers. These
are carnivore-eating carnivores, like eagles, lion,
tigers and leopard.
Lion feeding on another carnivore(dog)
QUESTIONS
Where will you place omnivorous organisms-plants and flesh eaters in the
energy transfer level?
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⚫
Decomposers: these are fungi and bacteria that obtain their energy by
breaking dead and decaying organic matter i.e. that eat dead matter a
waste product from the other various levels. Other decomposers are
detritivores—detritus eaters or debris eaters. These are usually multicellular
animals such as earthworms, crabs, slugs, or vultures.
Decomposers as a group play a critical role in keeping ecosystems healthy.
When they break down dead material and wastes, they release nutrients that
can be recycled and used as building blocks by primary producers
Producer
primary consumer secondary consumer
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The arrow shows the direction of energy flow in the food chain.
QUESTIONS
1. What is the major source of energy in an ecosystem?
2. Explain the following terms
a. primary producers b. Consumers c. Food chain
3. Construct a food chain using any four of the organisms listed below;
Goat, lizard, bird, snake, earthworm, grass cutter, grass, ant and cassava.
1.2 FOOD WEB.
Food web is a complex feeding relationship consisting of many food chains
linked together to a network.
Food web shows the interactions between organisms across trophic levels.
Arrows point from an organism that is consumed to the organism that
consumes it.
Figure 1.1 a diagram of food web
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As the food web above shows, some species can eat organisms from more
than one trophic level.
QUESTIONS
1. Explain how energy is transferred from one organism to the other in an
ecosystem
2. Briefly explain why as you move from one trophic level to another the
energy level decreases in an ecosystem.
SUMMARY
➢ The sequential flow of energy from one trophic level to another is
called food chain.
➢ Energy flows from primary producer to the tertiary consumer through
eating and been eaten.
➢ Primary producers make their own food in a process called
photosynthesis.
➢ In an ecosystem, an organism may belong to more than one food
chain.
LESSON 4: By the end of the lesson, student will be able to;
o Describe at least four activities that disrupt the balance in the
ecosystem.
o Discuss at five ways to maintain balance in nature
1.1 ACTIVITIES THAT DISRUPT THAT BALANCE OF THE ECOSYSTEM.
In balanced ecosystem, the abiotic factors interact with biotic factors in the
environment and their efficient flow of energy and material recycling and
interconnectedness between primary producers and consumers. Anything
affecting any factor of an ecosystem negatively can disrupt the ecosystem.
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An imbalance in an ecosystem occurs when one component of the
ecosystem becomes dominant, forcing out other components. For example, if
carnivores are eliminated from an ecosystem, then too many herbivores, for
example antelope, are allowed to grow to maturity and reproduce. The
growing number of herbivores deplete the plants, preventing them from
reproducing and thus leaving fewer offspring behind. Eventually, the
herbivores will begin to starve in large numbers, possibly even becoming
extinct in that region.
Natural disasters and some human activities that disrupt and threaten the
ecosystem are outlined below
Natural disasters include; earthquake, flooding, hurricanes, tsunamis,
volcanic eruption etc.
Natural disaster like tsunami destroys coral reef fish populations that leads to
the elimination of other species that depended on them as a food source,
while on land, the soil that was exposed to salt sedimentation, becomes
infertile, resulting in the loss of biodiversity in the form of coastal forests and
the animal life that they supported.
Floods, hurricanes and tornadoes destroy vegetation and kill animals which
disrupt the flow of energy in the ecosystem
Flooded area
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Earthquakes and volcanic eruption destroy lands, vegetation and kill animals
leading to disruption of the ecosystem.
Earthquake
volcanic eruption
SOME HUMAN ACTIVITIES THAT DISRUPT THE ECOSYSTEM
✓ Deforestation: Logging
operations, which provide the
world’s wood and paper
products, slush and burn
agriculture are the major
causes of deforestation.
Deforestation lead to loss of
habitats, loss of biodiversity
and change in climate. Trees
which are supposed to absorb carbon dioxide are cut down which
causes global warming are destroyed affecting the flow of energy in the
ecosystem.
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✓ Air pollution: Emission of toxic
substances like Sulphur oxide, carbon
dioxide and nitrogen oxide from
industries leads to formation of acid rain.
Acid rain affects plants and animal,
bringing disturbance in the ecosystem.
Polluted water
✓ Water pollution: dumping of rubbish and defecation into water bodies
leads to eutrophication-accumulation of nutrient that cause algae
blooms and consequently leading to loss of oxygen in the aquatic
habitat. Aquatic organisms die and lead extinction of aquatic species
which serve as food source for other organisms in the food chain. Illegal
mining introduces poisonous chemicals like mercury and cyanide
destabilise food chain and food web.
✓ Hunting can lead to the extinction
of some wild species and other
specific hunted species, especially
when not controlled. People hunted
three species of camel, woolly
mammoths and giant armadillos into
extinction in North America more
than 12,000 years ago. The University of Michigan predicts over hunting
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will be the cause of extinction in about 25 percent of all animal
extinctions during the 21st century. Extinction and endangering of some
species in the environment bring imbalance in the environment.
✓ Industrialisation and urbanisation: More habitats are destroyed due to
construction of roads, bridge, dams, house and other social amenities as
population increases.
✓ The use of pesticides and insecticides interfere with the ecosystem
because they kill organisms that enhance the flow of energy in the food
chain and food web. The life cycle of flowering plants is affected
because some animals that serve as agent of pollination and dispersal
are killed.
1.2 HOW TO MAINTAIN A BALANCE IN THE ECOSYSTEM
✓ There should be education on effects of destroying habitats and
destabilising the ecosystem.
✓ Law must be enforced to deal with people who cut tress indiscriminately
and hunt for wild animals.
✓ Trees and other plants species that are felled should be replanted.
✓ Proper waste management should be put in place to avoid
environmental pollution,
✓ Food farming methods like crop rotation and organic farming should be
encouraged.
✓ Natural parks and game reserves should must be protected.
QUESTIONS
1.
Describe four activities that disrupt the balance in the ecosystem.
2. Explain five ways in the balance in nature can be maintained.
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SUMMARY
➢ Natural disasters like earthquake, flooding, hurricane, volcanic eruption
disrupt the stability of the ecosystem.
➢ Human activities like deforestation, hunting, water pollution and water
pollution also disrupt how living and non-living thing interact with each
other.
➢ Natural and human activities lead to extinction and endangering of
species.
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UNIT 2: AIR POLLUTION
LESSON 1: By the end of the lesson, student will be able to;
o Define air pollution
o Define pollutants
o Explain four pollutants of air pollution.
1.1 DEFINITION OF AIR POLLUTION
Air pollution is the release of harmful substance into atmosphere that is
detrimental to human life and other living organisms. These harmful
substances are called pollutants.
1.2 AIR POLLLUTANTS
Air pollutant are harmful substances that released into the air that causes
harm to human and the environment. Most air pollutants come from the use
and production of energy especially fossil fuels. Some names of air pollutants
and their sources are outlined below;
✓ Sulphur dioxide: Sulphur dioxide is a poisonous invisible gas. The main
source of sulphur dioxide in the air is the processing of materials that
contain sulphur. Examples; generation electricity from coal, mining of
mineral ore that contain sulphur and volcanic eruption.
Venue volcanoes spewing Sulphur into the atmosphere
✓ Carbon monoxide: This a poisonous colourless, non-irritating and odourless
gas that is produced from incomplete combustion of fossil fuels such as
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natural gas and coal. Other sources include motor exhaust fumes,
tobacco smoke and volcanic eruption.
Carbon monoxide from car exhaust
✓ Nitrogen dioxide: Nitrogen dioxide get into the air from the burning of
fossil fuels such as coal and natural gas in factories and power station.
Most of the nitrogen dioxide are from motor exhaust fumes.
Nitrogen dioxide from power generation site
✓ Carbon dioxide: excess carbon dioxide in the air makes the air impure
and harmful. Carbon dioxide is released from fuel in the factories and
energy generation site, motor exhaust fumes and volcanic eruption.
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Carbon dioxide from factories.
✓ Dust and smoke: dust particles are released from quarries, factories,
construction and mining sites.
Dust particles from construction site
✓ Chlorofluorocarbon (CFC): chlorofluorocarbons contain chlorine, fluorine
and carbon. They are used in the manufacture of aerosol sprays and as
refrigerant in fridges.
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QUESTIONS
1. What is pollution?
2. What are air pollutants?
3. state the sources of the following air pollutants
a. Carbon monoxide b. Sulphur dioxide c. Nitrogen dioxide
4a. What is acid rain?
b. Give two effects of acid rain.
SUMMARY:
➢ Air pollutants are harmful substances released into the atmosphere that
causes harm to man and other living things.
➢ Most air pollutants are released from combustion of fuel.
➢ Air pollutants include; sulphur dioxide, carbon monoxide, nitrogen
dioxide, dust particles, carbon dioxide, chlorofluorocarbon etc.
LESSON 2: By the end of the lesson, student will be able to;
o Outline four effects of air pollution.
o Discuss four ways by which air pollution can be prevented.
1.1 HARMFUL EFFECTS OF AIR POLLUTANTS
✓ Sulphur dioxide: Sulphur dioxide affects human health when it is
breathed in. It irritates the nose, throat, and airways to cause coughing,
shortness of breath, or a tight feeling around the chest, diseases of the
lungs and bronchus. Sulphur react with water to form acid rain. Acid rain
increases the acidity of water and soil resulting in the death of living
organisms in the ecosystem. It also leads to corroding of metals and
damaging of buildings and statues
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✓ Carbon monoxide: when inhaled, carbon monoxide combines with
haemoglobin of the red blood cells to form carboxyhaemoglobin. This
prevents the red blood cells from carrying oxygen to the tissue for
respiration to occur. This can lead to a condition where the whole body is
depriving of oxygen (hypoxia) and even cause death.
✓ Nitrogen dioxide: When inhaled, leads respiratory disorders and diseases.
Nitrogen dioxide also react with water to form acidic rain which affect
humans and other living organisms in the environment.
✓ Carbon dioxide: The emission of high amount of carbon dioxide leads to
trapping excess heat escaping back into the atmosphere. This condition
is called greenhouse effect. The effect of heating up earth’s surface is
called global warming. Global warming lead to climate change: rising
sea levels, more extreme weather, heat-related deaths, and increasing
transmission of infectious diseases like Lyme.
✓ Chlorofluorocarbons: When chlorofluorocarbons rise into the atmosphere,
they destroy the ozone layer. The ozone layer protects us from the sun’s
harmful energy called ultraviolet ray. UV radiation causes various harmful
effects in humans, including skin cancer and cataracts, a clouding of the
lens of the eye.
Depletion of the ozone layer
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QUESTIONS
1. List four possible effects of air pollution.
2. What is greenhouse effect.
3. What causes the harmful ultraviolet ray from the sun to reach the earth’s
surface?
1.2 WAYS TO REDUCE AIR POLLUTION
✓ Plant more trees: Planting more trees will absorb the excess carbon
dioxide in the atmosphere to reducing heating up of the atmosphere.
✓ Alternative use of fuel: clean energy technologies like the use solar and
wind energy used be encouraged because they are environmentally
friendly.
✓ Enforcement of law: Environmental Protection Agency must make sure
that factories, companies and individual comply with the existing laws
and regulation on the environment.
✓ Filtering filters and absorbers should be in factories chimneys to reduce
the amount of air pollutants released into the atmosphere.
✓ Use special carburettors in motor vehicles, which produce small amount
of carbon monoxide.
✓ Motor vehicles with weak engines should be replaced with new and
efficient ones.
✓ There should be public education on the effects of releasing air pollutants
into the atmosphere.
QUESTION
What are some of the ways you can prevent air pollution in your society?
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SUMMARY:
➢ Air pollution leads to the formation of acid rain which intend affect
plants and animals.
➢ Respiratory diseases and disorder and global warming are effects of air
pollution.
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UNIT 3: PHYSICAL AND CHEMICAL CHANGE
LESSON 1: By the end of the lesson, student will be able to;
o Define physical change
o Determine the process of physical change
o Give at least four examples of physical change.
INTRODUCTION
Substances in nature undergo many changes. We see an ice block melting
when placed outside the freezer, burning of charcoal into ashes, water
boiling into vapour and vapour condensing to form water. All these changes
can be classified into two categories namely;
✓ Physical change
✓ Chemical change
1.1 PHYSICAL CHANGE
A physical change is a change in which the chemical composition of matter
is not altered. This means the same substances that were at the beginning of
the change are at the end of the change.
In physical change, there is no change in mass of the substance and it is
easily reversible. It is only the physical properties such colour, shape, texture,
temperature density of the substance that are changed.
For example, as an ice cube melts, its shape changes as it acquires the ability
to flow. However, its composition does not change. The melted ice cube
may be refrozen, so melting is a reversible. Melting is an example of a
physical change.
Another example is that when we heat the water, it changes to water
vapour. But even though the physical properties have changed, the
molecules are exactly the same as before. The water vapour can be
condensed to form water again.
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1.2 SOME OTHER FORMS OF PHYSICAL CHANGE INCLUDE:
✓ Changes of state (changes from a solid to a liquid or a gas and vice
versa)
✓ Separation of a mixture; distillation, sublimation, evaporation etc.
✓ Physical deformation (cutting, denting, stretching)
✓ Grinding of solid into powder
✓ Expansion and contraction of substance when heated or cooled.
QUESTIONS
1. Explain the term physical change.
2. How do you tell that a change in a substance is physical?
Activity
Carry out the following activities
a. Work in groups
b. Materials needed: ice block, a piece of paper, elastic band, football and
a pump
c.
Melt and freeze and ice block
d.
Crumple a piece of paper
e. Stretch an elastic band or catapult
f.
Inflate and deflate a bicycle tires or football
g. In each of the activity, observe the state of the material and see whether
you can reverse the state
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SUMMARY:
➢ A physical change is a change in which the chemical composition of
matter is not altered.
➢ In physical change, only the physical properties of the matter change.
➢ Physical change can easily be reversed.
LESSON 2: By the end of the lesson, student will be able to;
o Define chemical change
o Determine the process of chemical change
o Give at least four examples of chemical change.
o Give at least four differences between physical and chemical change
1.1 CHEMICAL CHANGE
A chemical change is a change in which there is alteration in the chemical
composition of matter. This means that the bond between the molecules of
matter is broken or formed. Chemical change release or absorb heat or
other energy or may produce a gas, odour, colour or sound. In chemical
change, new substance is formed and harder to reverse. The new substances
do not have the same chemical properties as the original one.
Activity
a. Work in groups
b. Material needed: an egg, an iron nail, water, a beaker, a piece of paper
and a match.
c. Boil an egg in a beaker of water for about 10 minutes.
d. Observe and record the changes
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e. Hold a piece of paper, light it with the match and allow it to burn.
f.
Observe and record the changes.
g. Put the iron nail in water and leave it for a few days
h. Remove the nail and observe the changes.
In each activity state whether the changes can be reversed.
1.2 OTHER EXAMPLES OF CHEMICAL CHANGES
✓ Digestion of food
✓ Fermentation
✓ Respiration
✓ Reaction of metal and limestone
✓ Adding water to cement powder
✓ Reaction of sodium with water
✓ Cooking of food
QUESTIONS
In each of the following activities state whether the changes that occur are
i.
Physical or chemical change
ii.
Reversible or irreversible
a. Some boiled cassava and plantain were pounded together into fufu
b. A piece of ice block put in a cup, after a while, it was found out that the
block had changed in to a liquid
c. A clean piece of nail was put into a beaker. After five days it was
observed that the colour of the nail had changed.
1.3 DIFFERENCES BETWEEN PHYSICAL AND CHEMICAL CHANGE
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Physical change
Chemical change
No new substances are formed
New substances are formed
Easily reversible
Not easily reversible
There is no change in mass
There is change in mass
Not usually accompanied with great
heat
Usually accompanied with great
heat
QUESTIONS
Label each of the following changes as a physical or chemical change. Give
evidence to support your answer.
a)
Breaking a bottle
b)
Boiling water
c)
Evaporating alcohol
d)
Shredding paper
e)
Breaking a bottle
f)
Boiling water
g)
Evaporating alcohol
h)
Boiling water
i)
Evaporating alcohol
SUMMARY
➢ A chemical change is a change in which there is alteration in the
chemical composition of matter.
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➢ In chemical change, bond between molecules are broken or formed.
➢ It is harder to reverse chemical change.
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END YEAR 7 OBJECTIVE TEST
1.
A van of mass 200kg is travelling from Accra to Kumasi. What is its
kinetic energy if it is travelling at 10m/s?
A.10000J
B. 1000J
C.100000J
D. 100J
2. Which of the following organisms is a primary producer?
A. eagle
B. goat
C. grass
D. lion
3. The word meniscus refers to………………………
A. the volume of liquid
B. the mass of water
C. the curved surface of a liquid
D. the density of a liquid
4. The basic unit of matter is…………………………
A. compound
B. atom
C. molecules
D. mixture
5. All the following can be found in animal cells except
A. nucleus
B. mitochondrion
C. vacuole
D. chloroplast
6. The structures in the human respiratory system where exchange of gases
occur is…
A. trachea
B. bronchus
C. alveoli
D. larynx
7. The total number of organisms of the same species is called…………
A. population
B. community
C. habitat
D. ecosystem
8. Which of the following structures helps tilapia to exchange gases?
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A. pectoral fins
B. gills
C. operculum
D. pelvic fins
9. Materials that allow all light to pass through them are called……
A. translucent
B. opaque
C. transparent
D. florescence
10. Organisms that can interbreed and produce fertile offspring is called…
A. population
B. species
C. community
D. population density
11. The modification of behaviours and characteristics of organisms to help
them live
successfully in their habitat is term as…….
A. adoption
B. adaptation
C. variation
D. population
12. Which of the following is true about weight.
A. it is a vector quantity
B. it is a scaler quantity
C. it is measured by beam balance D. it is measured by a ruler
13. Which part of the cell controls al the activities of the cell?
A. chloroplast
B. cell membrane
C. nucleus
D. mitochondrion.
14. The process by which water is changed to steam is called………
A. condensation
B. evaporation
C. melting
D. sublimation
15. The component of the soil which is made up of the finest particles is
A. Humus
C. Sandy
B. Clay
D. Loamy
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Study the hazard symbols carefully and use them to answer question 16-18
I
II
III
IV
16. Which of the above symbols represent toxic?
A. I
B. III
C. IV
D. II
17. Which of the symbols would you place on a concentrated
tetraoxosulphate(IV) acid?
A. II
B. III
C. I
D. IV
18. Which of the symbols is a prohibition symbol?
A. III
B. I
C. IV
D. II
19. A fertilised ovule results in the formation of .......
A. Embryo
B. Stigma
C. Pistil
D. Ovary
20. A viable is seed is a……...
A. death seed
B. healthy seed
C. deformed seed
D. wet seed
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21. The practice of removing excess branches, flower buds and infected
parts of the plant is referred as ………………...
A. pruning
B. cutting
C. weeding
D. clearing
22. Leguminous crops are included in crop rotation to ………………….
A. fix nutrient into the soil
B. prevent soil aeration
C. to prevent the activities microorganisms in the soil
D. scare pests
Respiration is a chemical reaction that occurs inside a living cell. Study the
word equation below and use it to answer question 23-25
glucose + ...........ß........... → carbon dioxide + ........ρ................+……θ………...
23. Which compounds are represented by the Greek symbols ρ and θ
respectively?
A. oxygen and water
B. water and carbon monoxide
C. water and energy
D. oxygen and energy.
24. The symbol ß represent……………..
A. water
B. oxygen
C. carbon monoxide
D. energy
25. What type of respiration is represented by the equation?
A. anaerobic respiration
B. aerobic respiration
C. breathing
D. excretion
26. Which of the following energy changes takes place when a church bell is
tolled?
A. potential energy to kinetic energy
B. kinetic energy to sound energy
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C. potential energy to sound energy
D. chemical energy to heat energy
27. A car battery produces electrical energy from…………………...
A. kinetic energy
B. heat energy
C. chemical
D. potential energy
28. The change in direction of light as it travels from air to water is
called………
A. deflection of light
B. refraction of light
C. reflection of light
D. absorption of light
29. An insulating material that separates the two-metal plates in a capacitor
is called……
A. nonelectric
B. dielectric
C. semiconductor
D. electric
30. The process of applying voltage to a P-N junction diode is called……….
A. reversing
B. biasing
C. doping
D. charging
31. Oxygen in the air is able to get into the blood by…………
A. capillarity
B. diffusion
C. osmosis
D. surface tension
32. A ray of light makes an angle of 200 with the surface of a plane mirror.
Determine the angle of reflection.
A. 200
B. 500
C.700
D.900
33. All the following are life processes except…………
A. Nutrition
B. Respiration
C. Egestion
D. Excretion
34. The boiling point of water is…………….
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A. 200K
B. 273K
C. 373K
C. -373K
35. All the following are fundamental quantities except
A.
Mass
C. Length
B. Time
D. Force
37. A stop watch is used to measure…………………
A. time
B. quantity of a watch
C. distance covered by a car
D. length
38. The part of a plant which is found in the soil is called
A. flower
B. root
B branches
D. stem
39. The removal of waste product from the cells of organisms is called
A. absorption
B. excretion
C. exhalation
D. assimilation
40. Which of the following organelles contains chromosomes?
A. Nucleus
B. Mitochondrion
C. Vacuole
D. centriole
41. Which of the following is a base unit?
A. m
C. m3
B. mm
D. kg/m3
42. What is the potential of energy of an object of mass 5kg placed on a
table of height 3m. {take g= 10m/s2}
A. 15.0J
B. 15000J
C. 150.0J
D. 1500.00J
43. Mass is defined as the………………...
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A. the amount of space occupied by a matter
B. weight of an object
C. the quantity of matter in an object
D. the movement of an
object
44. Seconds is the unit for measuring……...
A.
Length
B.
C Weight
D.
time
volume
45. The green pigment found in the leaf of a plant responsible for trapping
solar energy for photosynthesis is found in the……...
A. Chromosome
B. Chloroplast
C. Nucleus
D. mitochondrion
46. Which of the following occupies the first trophic level in a food chain?
A. primary consumers
B. secondary consumers
C. primary producers
D. tertiary consumer.
47. A farming system where the farmer produces crops and rears animals on
the same known as
A. shifting cultivation
B. mixed farming
C. mixed cropping
D. livestock farming
48. Carnivores that eat herbivores are called………
A. primary consumers
B. tertiary consumers
C. secondary consumers
D. primary producers
49. Which of the following organelle is responsible for the production of
energy?
A. Chloroplast
B. Mitochondrion
C. Vacuole
D. Lysosome
50. The process of applying voltage to a P-N junction diode is called……….
A. reversing
B. biasing
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C. doping
D. charging
51. Which of the following substance sublimes when heated gently?
A. Carbon
B. Sulphur
C. Naphthalene
D. Candle
52.Which of the following is not a characteristic of image formed on a
pinhole camera?
A. it is diminished
B. it is inverted
C. it is real
D. it cannot be
formed on a screen
53. Which of the following is not an agent of dispersal of fruits and seeds/
A. water
B. explosive mechanism
C. carbon dioxide
D. Wind.
54. The brightly coloured petals of a flower…...
A. attract insect
B. beautify the plant
B. drives insect awayD. make the plant very strong
55. The eclipse of the sun occurs when………………….
A. the sun comes between the moon and the earth
B. earth and moon in a straight line
C. earth is between the sun and the moon
D. moon and planets are in a straight line.
56. When a light travel from air to water, the light will
A. bend towards the normal
C. bend away from the normal
B. bend into the normal
D. be in a straight line
57. The full meaning of L.E.D as applied in electronics stands for…...
A. Light Emission Diode
B. Light Emitting Diod
C. Light Emitting Diode
D. Light Emitting Dielectric
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58. The linear sequence of living organisms feeding and being fed on is
called…..
A. food web
B. food chain
C. decomposing
D. feeding habit
59. Which of the following is the organic part of the soil?
A. clay soil
B. sandy soil
C. loamy soil
D. humus
60. The normal body temperature of healthy person is about……
A. 360C
B. 370C
C. 350C
D. 35.50C
61. Mass per unit volume of a substance describes its……
A. weight
B. density
C. height
D. temperature
62. The knowledge acquired through the study of science is termed as….
A. scientific knowledge
B. scientific method
C. scientific data
D. hypothesis
63. A piece of wood of mass 100g was gently immersed into a measuring
cylinder containing water. If the level of water rose by 20 cm3. What is its
density
A. 4g/cm3
B. 5g/cm3
C. 6g/cm3
D. 3g/cm3
64. The outer covering of a seed is called…….
A. micropyle
B. plumule
C. testa
D. hilum
65. Which of the following is a biotic factor of the ecosystem?
A. parasite
B. soil
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C. water
D. temperature
66. The darkest part of a shadow formed when during an eclipse is called…
A. umbra
B. penumbra
C. eclipse of the sun
D. eclipse of the moon
67. The voice box is also called
A. pharynx
B. thorax
C. epiglottis
D. larynx
68. Which eye glasses would prescribe for a person who cannot see distant
object?
A. converging lens
B. diverging lens
C. google
D. white glass
69. An imbalance in the ecosystem occurs when one of the components
becomes…
A. dominant
D. producer
B. consumer
D. decomposer
70. Which of the following can exist in the three state of matter?
A. Oil
B. Gasoline
C. Alcohol
D. Water
71. Which of the following is cellulose found?
A. Cell wall
C. Chloroplast
B. Cell membrane
D. Nucleus
72. The part of the soil profile where most soil living organisms are found is
A. B horizon
B. C horizon
C. D horizon
D. A horizon
73. Which of the following components of electronics stores electrical
charges?
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A. resistor
B. capacitor
C. diode
D. LED
74. Which of the following is not a condition necessary for germination to
occur?
A. water
B. light
C. oxygen
D. suitable temperature
75. The trachea is also known as…………………
A. Adam’s apple
B. windpipe
C. air sacks
D. breathing tube
78. The energy stored in food is ………………………….
A. chemical energy
B. solar energy
C. thermal energy
D. kinetic energy
79. The type of soil which becomes water-logged after rainfall is made up of
a large
amount of……………
A. silt
B. sand
C. gravel
D. clay
80. The process by which living things increase in number is
called………………….
A. Growth
B. Nutrition
C. Reproduction
D. Excretion
81. The practice of growing crops and rearing animal for human
consumption is called
A. farming
C. tilling
B. pharming
D. cropping
82. When water vapour cools down, it changes into….
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A. liquid water
B. ice blocks
C. steam
D. ice cubes
83. Which of the following change of state of matter requires absorption of
heat?
A. condensation
B. sublimation
C. freezing
D. deposition
84. A fertilised ovum is known as………
A. a zygote
B. an embryo
C. an offspring
D. a gamete
85. The scattering of fruits and seeds from their parent plants is called……
A. propagation
B. transplanting
C. dispersal
D. broadcasting
86. The formation of shadows shows that………
A. light can be refracted
B. light travels in a straight line
C. light can be reflected
D. light can be absorbed.
87. A semiconductor material that allows current to flow in only direction is
called…
A. P-N junction diode
B. capacitor
C. resistor
D. integrated circuit
88. Which of the following equations represents ohms law
A. V+R=I
B. V=IR
C. V+I=R
D. V=I=R
89. Primary producers are also known as………………...
A. heterotrophs
B. autotrophs
C. detritivores
D. scavengers
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90. The transfer of pollen grains from the anther to the stigma of a flower is
knowns as...
A. dispersal
B. broadcasting
C. pollination
D. fertilisation
91. In an ecosystem, decomposers are not needed. True/False
92. The cell is the smallest unit of a living organism. True/ False
93. Herbivores occupy the second trophic level in a food chain. True/ False
94.The basic unit of matter is ……………………
95. Aerobic respiration occurs in the absence of oxygen. True/ False
96. The unit of measurement of energy is…………………………
97. Rectilinear propagation of light
means……………………………………………….
98. The potential energy of a body is given by
………………………………………………
99. Human being can be both primary and secondary consumer. True/ False
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