Biology 1 to 4

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Biology: 1. Living Things
Syllabus
OB38 Understand how to use a simple key to identify plants and animals, including vertebrates and invertebrates
OB39 Investigate the variety of living things by direct observation of animals and plants in their environment;
classify living organisms as plants or animals, and animals as vertebrates or invertebrates
OB40 Identify the basic life processes and characteristics common to all living organisms: nutrition, respiration,
excretion, growth, reproduction, movement and response
OB41 Recall that living things are composed of cells, tissues, organs and systems, and understand that growth results
from cell division
Student Notes
Biology is the study of living things (called organisms)
The living things which we are most familiar with are plants and animals.
Plants
Make their own food
Do not move from place to place
Have cell walls
Animals
Do not make their own food
Move from place to place
Do not have cell walls
Animals can then be sorted into two groups:
1. Vertebrates = Animals that have a backbone. (Mammal, fish, bird, reptile, amphibian).
2. Invertebrates = Animals that do not have a backbone. (Spiders, worms, jellyfish, anemones, etc).
Biology Keys
A key in Biology is a set of instructions which help us to
identify or classify an organism.
The key on the right helps us to identify classify different
types of vertebrates.
Can you identify where humans fit into this map?
Basic life processes and characteristics common to all
living organisms
All living things have 7 life processes or characteristics in
common. These are:
1. Growth
All living things can grow/increase in size.
This happens through cell division where cells have the ability to make copies of themselves.
2. Movement
All living things can move. Animals can walk, fly etc, plants move their parts.
3. Nutrition
All living things must be able to take in material from their environment such as food, which is needed to produce
energy.
4. Respiration
All organisms must extract energy from the food that they consume. Aerobic respiration uses oxygen to obtain
energy from food.
5. Excretion
Getting rid of waste products from chemical reactions in the body.
6. Response
Reacting to a stimuli or changes in the environment.
7. Reproduction
The formation of new individuals.
Organisms must be able to reproduce themselves or their species will become extinct.
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All organisms are composed of cells which form tissues which form organs which in turn form systems.
Cells
Cells are the main building blocks of life, e.g. blood cells and skin cells.
(We will look at them in detail in the next chapter).
Tissues
A tissue is made up of a group of similar cells which carry out the same function, e.g. skin tissue and muscle tissue.
Organs
An organ is made up of different types of tissue working together, e.g. the heart and the lung.
Systems
A system is formed by a group of organs working together, e.g. the reproductive system and the digestive system.
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Exam Questions
1. [2008 OL]
(i) Write the letter T opposite the name of a body tissue in the table on the right.
(ii) Write the letter O beside the name of a body organ in the table on the right.
2.
[2009 OL][2007 OL]
Choose one vertebrate and one invertebrate from the list of animals on the
right.
Snail
Frog
Thrush
Earthworm
3. [2009 OL]
(i) Choose the correct temperature range of human body temperature from the list on the
right.
(ii) Give one reason for a change in body temperature.
4. [2008 OL]
The table shows a simple key used to identify
some common organisms found in a habitat.
In the case of any two of the organisms
shown on the right, write the letter
corresponding to a key feature given in the
table above beside the organism which that
best describes.
Letter
A
B
C
D
Key feature of organism
Four pairs of legs
Segmented body, no legs
Three pairs of legs
Eight to ten pairs of legs
Other Test Questions
1. List six characteristics of living things.
2. What is an organ made up of?
3. Define (i) sensitivity, (ii) reproduction, (iii) respiration and (iv) excretion.
4. Explain the term tissue.
5. What process do cells undergo to allow growth in organisms?
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36 – 370 C
86 – 870 C
Muscle
Digestive
system
Heart
Biology: 2. Animal and Plant cells
Syllabus
OB42 Identify, and understand the functions of, the main parts of a microscope (light microscope only) and use it to
examine an animal cell and a plant cell
OB43 Draw one example each of an animal cell and a plant cell, identifying the nucleus, cytoplasm and cell wall
(plant cell), and indicate the position of the cell membrane
OB44 Prepare a slide from plant tissue and sketch the cells under magnification
Student Notes
The microscope
Organisms (living things) are made up of cells. Cells differ in shape, size and function.
The microscope can be used to examine plant and animal cells.
Component
Eyepiece
Function
Magnifies the image
Focus wheels
Focuses the image
Objective lenses
Magnifies the image
Stage
Supports the Slide
Slide
The specimen is placed on
the slide
Light source
Light-bulb
To prepare plant cells for viewing under a microscope
1. Place a drop of iodine onto a clean glass slide (iodine is used to stain (‘dye’) a cell and make it easier to see).
2. Cut an onion and remove a thin layer of inner cells.
3. Place it on the slide and place a cover slip on top.
To prepare animal cells for viewing under a microscope
1. Use a cotton swab to get cheek cells and smear this onto a slide.
2. Put a couple of drops of methylene blue stain on the smear and leave for a few mintues.
3. Rinse off the stain and allow the slide to dry.
To examine a plant or animal cell under a microscope
1. Put a piece of tissue on the slide and cover it with a glass slip.
2. Place the glass slide on the stage and secure with clips.
3. Watch from the side and turn the coarse focus wheel so that the objective lens is as close to the stage as possible.
4. Put your eye to the eyepiece and gently turn the fine focus wheel the opposite way to sharpen the image.
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Animal Cell
Plant Cell
Part
Cytoplasm
Function
Most of the cell’s activities happen here
Cell membrane
Nucleus
Holds in the contents of the cell and controls what enters and
leaves the cell
Controls the activities of the cell
Vacuoles
Store food
Cell wall
Provides support and structure to plant cells
Chloroplasts
These contain chlorophyll which makes food for plant cells
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Exam Questions
1. [2007 OL]
The picture shows a piece of laboratory equipment.
(i) Name the piece of equipment.
(ii) Give one use of this piece of equipment.
2. [2009]
The parts labelled A and B in the diagram of the microscope work together to perform a single
function.
(i) What is the combined function of A and B?
(ii) Name the part labelled C in the diagram.
3. [2008 OL]
The diagram shows a microscope.
Study the diagram and answer the questions below using the table.
(i) In the table write the letter A beside the name of the part labelled A.
(ii) In the table write the letter B beside the name of the part labelled B.
(iii) In the table write the letter C beside the name of the part labelled C.
(iv) In the table write the letter F beside the function of the part labelled B.
Lens
Lamp
Eye piece
Focus wheel
Base
To focus
To magnify
4. [2006]
The diagram shows a laboratory microscope.
What are the functions of parts labelled A and B?
5. [2006]
Onion epidermis is a tissue only one cell thick.
It is used in school laboratories on microscope slides to investigate plant cell structure using a
microscope.
Describe how to prepare a microscope slide from a plant tissue.
6. [2006]
Draw a labelled diagram of a plant cell.
7. [2008 OL]
The diagram shows an animal cell and a plant cell.
(i) Write the letter P beside the plant cell in the table on the right.
(ii) Write the letter A beside the animal cell in the table on the right.
Other Test Questions
6. Draw a labelled diagram of a microscope including all major parts.
7. Draw a labelled diagram of an animal cell.
8. Draw a labelled diagram of a plant cell – include nucleus, vacuole, cell wall cell membrane cytoplasm,
chloroplast.
What is the function of each part?
6
Biology: 3. Food
Syllabus
OB1 Recall that a balanced diet has six constituents: carbohydrates (including fibre), fats, proteins, vitamins,
minerals and water, each with different functions
OB2
Describe a food pyramid and give examples of types of food recommended in a balanced diet.
OB3
Carry out qualitative food tests for starch, reducing sugar, protein and fat
OB4
Read and interpret the energy values indicated on food labels and compare the energy content per 100 g of a
number of foods, and identify the food types on the label that form part of a balanced diet.
OB5
Investigate the conversion of chemical energy in food to heat energy
Student Notes
Why do humans need food?
We need food for energy to help us grow and to repair worn down or damaged parts of our bodies.
Food types
1.
2.
3.
4.
5.
6.
Six Types
Carbohydrates
Fats
Proteins
Vitamins
Minerals
Water
Nutrient
Functions
Common Sources
Carbohydrates
e.g. Sugars, starch and
fibre
Supplies energy, prevents
constipation!
Fruits, Honey
Bread, Potatoes
Rice, Fruit & Vegetables
Fats
Provides energy and insulation
Dairy products
Proteins
Growth and repair.
Meat, Fish, Eggs, Milk, Cheese
Vitamins
e.g. Vitamin D, Vitamin
C
Minerals
e.g. Fluorine, Calcium,
Iron
Water
e.g. Evian, Ballygowan
Healthy skin and bones
Fruit, Green Vegetables,
Potatoes, Beans, Milk
Healthy teeth and bones, prevents
anaemia.
Green Vegetables, Red Meat
Dairy products
Allows cells to function
Can be obtained from special
bottles in a shop
Balanced Diet
A balanced diet contains the right amount of each of the six different types of food
A food pyramid helps us to determine the correct amount of each food type to maintain in a balanced diet.
Foods in a food pyramid are classified into five main groups:
From bottom to top
1. Cereals, e.g. bread and potatoes
2. Fruit and Vegetables
3. Dairy Products
4. Meat and Fish
5. Other
The bottom foods should be eaten often while those at the top should be
eaten sparingly.
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Failure to eat a balanced diet may cause a person to become overweight, tired, and slow and due to a lack of iron they
may result in having a condition called anaemia.
Energy Values
Different foods contain different amounts of energy.
These amounts are known as Energy Values.
Energy is measured in Joules (J).
However energy values of a food can be measured in Kilojoules per
gram (kJ/g).
Food Tests
Food Tested
Starch
Chemicals Used
Add iodine
Positive Result
Turns blue-black
Reducing sugar
e.g. glucose
Fat
Add Benedict’s solution
and heat
Rub food on brown
paper
Add sodium hydroxide
and then copper sulfate
Turns brick-red
Protein
Translucent Stain
Turns purple
To investigate the conversion of chemical energy in food to heat energy
1. Place a burning cream-cracker or peanut under a test-tube containing water.
2. Note the temperature of the water before and after.
3. The temperature of the water rises.
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Exam Questions
1. [2008]
Give one function for vitamins in our bodies.
2. [2008]
Give one function for minerals in our bodies.
3. [2006 OL]
Name the mineral needed for healthy growth of teeth.
4. [2007 OL]
Fibre is a carbohydrate and it is an important part of a balanced diet.
What is the function of fibre as part of a balanced diet?
5. [2007 OL]
Protein and carbohydrate form part of a balanced diet.
(i) In the table on the right write the letter P beside a good source of protein.
(ii) Write the letter C beside a good source of carbohydrate.
6. [2009 OL]
Proteins, fats and carbohydrates form part of a balanced diet.
Answer the following questions about food types.
(i) In the table write the letter F beside a good source of fat.
(ii) Write the letter C beside a good source of carbohydrate.
(iii) Give one function of fibre in the diet.
7. [2007]
Name the principal food type (nutrient), which is present in all of the foods shown.
8. [2006 OL]
The diagram shows a food pyramid.
(i) Name one item of food that could be found at X in the pyramid.
(ii) Why should only a small amount of the foods at the top of the pyramid be eaten?
9. [2006]
The diagram shows a food pyramid.
Explain how to use a food pyramid to plan a healthy diet.
10. [2007]
Describe a test to show the presence of fat.
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11. [2006]
Tests were carried out on three foods by a pupil
in a school laboratory.
The results of these tests are given in the table.
A plus (+) sign means a positive result to a test.
A minus (–) sign means a negative result to a
test.
(i) Which one of the foods, A, B or C would most likely be cheese, meat, or fish?
(ii) Which one of the foods, A, B or C would most likely be crisps, or chips?
12. [2008 OL]
The table shows the nutritional information given on the labels
on two foods A and B.
(i) Which food, A or B, provides the most energy per 100 g?
(ii) Which food, A or B, is more likely to be cheese?
Give a reason for your answer.
13. [2006]
This nutritional information was given on a packet of wheat bran.
Wheat bran is used with breakfast cereals and is added to brown
bread.
Select any two nutrients from the list given and say what role
each one has in maintaining health.
14. [2006 OL]
Describe an experiment you could carry out to show the
conversion of chemical energy to heat energy.
Draw a labelled diagram of any equipment used.
15. [2007]
Describe a simple laboratory experiment to show the release of chemical energy from food as heat.
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Other Test Questions
1. List six different food types.
2. Give an example of each of the food types above.
3. Give a function of each of the food types above. You should answer each of these questions by using a table with
three columns; entitled Type, Source and Function.
4. How can you test for the presence of starch in food.
5. What do you need to test for
(i) Starch ____________________________________________________________________
(ii) Reducing sugars____________________________________________________________
(iii) Fats _____________________________________________________________________
6. Fill in the table listing all the main food types in one column, a source of that food in the next column and the
main function of that food-type in the final column.
Type
Source
Function
7. Use the table below to answer the following questions:
Name the chemicals needed to test for protein, reducing sugars, starch and fat.
Give the results of each test.
Name a food for each test that would give a positive result.
Food tested
Chemical(s) used Positive results
Food source that
gives a positive
result
Protein
Reducing sugar
Starch
Fat
8. (i) Name a food which is a good source of roughage/fibre.
(ii) Why is it important to have a balanced diet?
(iii) Name a mineral and a vitamin found in dairy products which are needed for healthy bones.
(iv) Describe an experiment to compare the amount of energy in different food samples. Include a labelled
diagram.
(v) What units is energy in food measured in?
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Biology: 4. The Digestive System
OB6
Syllabus
Identify and locate the major parts of the digestive system including the mouth, oesophagus, stomach, liver,
pancreas, small intestine and large intestine, and know their functions.
OB7
Identify molars, premolars, canines and incisors, and describe their functions
OB8
Investigate the action of amylase on starch; identify the substrate, product and enzyme
Student Notes
Diagram of the human digestive system
Part
Mouth
Function
Physical digestion
Oesophagus
Passes food to the stomach by peristalsis
Stomach
Physical and chemical digestion
Small intestine
(6 metres long)
Pancreas
Chemical digestion and the absorption of
nutrients into the blood
Contains digestive enzymes
Liver
Produces Bile (for the digestion of fats)
Large intestine
Absorption of water from the food remains
Rectum
Faeces is stored in the rectum
Teeth
A full adult set of teeth contains 32 teeth
Tooth
Incisors
Canines
Premolars
Molars
Function
Biting and cutting
Grasping and tearing
Grinding and crushing
Grinding and crushing
Enzymes
A catalyst is a chemical that speeds up a chemical reaction.
An enzyme is a biological catalyst.
The substance an enzyme acts on is the substrate and the substance formed by the reaction is the product.
Amylase is an example of an enzyme and is used to break down starch into a reducing sugar called maltose.
Therefore in this case starch is the substrate and sugar is the product.
Amylase is found in saliva.
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To demonstrate the action of salivary amylase on starch
1. Add some saliva (which contains the amylase enzyme) to a starch solution which is in a test tube.
2. Heat in a water bath at 37 0C for 10 minutes.
3. The starch should now be converted to a simple sugar called maltose so we need to test for this.
Add some Benedict’s solution and place in boiling water for a few minutes.
4. The contents of the test-tube should turn red, indicating that sugar is present.
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Exam Questions
1. [2006 OL]
Digestion of food is important so that we can obtain energy from our food.
Name the parts of the digestive system labelled A, B and C in the diagram.
2. [2006 OL]
Give one function of the stomach.
3. [2007]
Give a digestive function of the liver.
4. [2007 OL]
The diagram below shows the human digestive system.
Examine the diagram and answer the questions that follow.
(i) In the table write the letter A beside the name of the part labelled
A.
(ii) Write the letter B beside the name of the part labelled B.
(iii) Write the letter F beside the function of the part labelled B.
5. [2007 OL]
The large intestine is labelled C in the diagram.
6. [2007 OL]
Fibre is a carbohydrate and it is an important part of a balanced
diet.
What is the function of fibre as part of a balanced diet?
7. [2007]
Give a function of the small intestine other than digestion.
8. [2006 OL]
Identify the type of tooth labelled X in the diagram on the right.
9. [2006 OL]
Name the mineral needed for healthy growth of teeth.
10. [2007 OL]
Two teeth are labelled T in the diagram.
In the table on the right write the letter T beside the type of tooth
labelled T.
Write the letter F beside the function of that type of tooth.
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11. [2009 OL]
A tooth is labelled T in the diagram.
(i) Write the letter T beside the type of tooth labelled T.
(ii) Write the letter F beside the word on the right which describes the function of this
type of tooth.
12. [2006 OL]
Salivary amylase found in the mouth acts on starch in the food we eat.
This action can be investigated in the laboratory.
Name the chemical used to test for the presence of starch at the beginning of the
experiment.
13. [2006 OL]
When salivary amylase is added to starch solution and the mixture placed in a water bath at 37 °C for 5 minutes, a
new product is formed.
Name the product formed.
14. [2006 OL]
A chemical is used to test for the presence of maltose. This chemical reacts with maltose to produce a brick-red
colour when they are heated together in a hot water bath for 5 minutes.
Name this chemical.
15. [2007]
In the small intestine starch is broken down to maltose by amylase.
Identify the enzyme, and the substrate named in this reaction.
16. [2008 OL]
In the table write the letter S beside the name of the solution used to test for the presence of a
reducing sugar.
17. [2008 OL]
In the table write the letter R beside the name of a reducing sugar.
18. [2008 OL]
In the table write the letter B beside the colour of the test solution used at the beginning of the
experiment.
Write the letter E beside the colour of the test solution that indicates a positive result for the
presence of a reducing sugar.
Biuret
Benedict’s
Fehling’s
Glucose
Sucrose
Brown
Blue
Brick Red
19. [2008]
A pupil performed an experiment in a school laboratory to show the action of a digestive enzyme on a food
substance.
(i) Name an enzyme suitable for such an experiment.
(ii) Name a food substance on which the enzyme that you have named will act.
(iii) Describe any preparation of the food required before the experiment is performed.
(iv) If no preparation is required state why.
(v) Give the temperature at which the enzyme-food mix should be maintained for the experiment to work.
(vi) How much time is needed for digestion of the food in this experiment?
(vii)
Describe a test to confirm that digestion has occurred.
20. [2007]
Describe a simple laboratory experiment to show the release of chemical energy from food as heat.
15
Class Questions
9. List the four types of teeth and give the function of each using the table provided:
Type of tooth
Function
1
2
3
4
10. Give the function of each of the following in the table provided:
Body Part
A
Mouth
B
Oesophagus
C
Stomach
D
Liver
E
Pancreas
F
Small intestine
G
Large intestine
Function
11.
(i) Identify each of the parts of the digestive system in the diagram by
putting the appropriate letter from Question 2 beside each part.
(ii) Mark on the diagram where digestion, absorption and egestion
occur.
12.
(i)
(ii)
(iii)
(iv)
(v)
What is an enzyme? Name the substance on which an enzymes
acts?
Describe an experiment to show the action of amylase on starch –
include a labelled diagram.
Give the results after testing each test-tube with iodine.
What is the product after amylase acts on starch?
How would you identify the substrate, product and enzyme?
16
OB9
Biology: 5. Respiration and Breathing
Syllabus
Describe the process of aerobic respiration by means of a word equation and understand that aerobic
respiration requires the presence of oxygen
OB10 Demonstrate the products of aerobic respiration
OB11 Carry out qualitative tests to compare the carbon dioxide levels of inhaled and exhaled air
OB12 Describe how oxygen is taken into the bloodstream from the lungs and how carbon dioxide is taken into the
lungs from the bloodstream during gaseous exchange and how these processes are affected by smoking
Student Notes
Respiration
Respiration is the controlled release of energy from food
Respiration is not the same as breathing!!
Respiration can be either aerobic or anaerobic.
Aerobic respiration requires oxygen while anaerobic does not.
Humans and all other animals carry out aerobic respiration while many micro-organisms like yeast carry out anaerobic
respiration
Equation for aerobic respiration
Glucose + oxygen → Energy + carbon dioxide + water
Test for CO2
It turns limewater milky.
Test for water
It turns cobalt chloride paper pink / it turns copper sulphate blue.
To show that there is more carbon dioxide in exhaled air than in inhaled air.
1. Suck air in through the position shown on diagram A
and note that the limewater takes a long time before
going milky.
2. Replace the limewater and this time exhale air
through the top of the tube as shown in diagram B
and note that the limewater goes milky quickly.
3. Conclusion: there is more carbon dioxide in exhaled
air.
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Breathing happens when animals take in oxygen and give out carbon dioxide and water
How does air enter and leave the lungs?
1. Diaphragm and intercostals muscles contract, pulling the
ribcage down.
2. The ribcage is attached to the lungs and as a result the volume in
the lungs increases causing the pressure to decrease.
3. Hence air is taken in to balance the pressures when the mouth
(or nasal passage) is open.
4. In order to exhale, the diaphragm relaxes, pushing the ribcage
up, reducing the volume of the lungs therefore increasing the
pressure, so if the mouth is open air will escape.
Gaseous exchange:
How oxygen is taken into the bloodstream and carbon dioxide
and water leave the bloodstream
Air passes in and out of the lungs, via the trachea (windpipe), bronchi and bronchioles.
The diagram shows tiny air sacs called alveoli (singular alveolus).
Each alveolus is surrounded by tiny blood vessels called capillaries.
Gaseous exchange takes place here.
Oxygen passes from the alveoli into the blood which is flowing through the
capillaries,
Carbon dioxide and water pass in the opposite direction; from the bloodstream
back into the alveoli where they are exhaled back out of the body.
The effect of smoking
Smoking has many adverse health effects, including cancer, heart disease,
pneumonia and bronchitis.
It clogs up the hairs in the nose, which reduces their effectiveness to filter incoming dust particles.
It also clogs up the alveoli in the lungs, reducing the ability to exchange gases.
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