CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 1.1
Completing sentences about respiration
Every living organism needs energy. They get their energy from glucose. and other nutrients.
The energy is released from the nutrients by chemical reactions in cells, called aerobic respiration.
During these reactions, the glucose is combined with oxygen. Oxygen is transported to our cells
by red blood cells. These cells contain a red pigment called haemoglobin.
Oxygen enters the blood in the air sacs in the lungs. The oxygen moves from the air into the blood by
diffusion. Carbon dioxide moves in the opposite direction. This is called gas exchange.
Worksheet 1.2
Explaining the meanings of words
Look for answers written in learners’ own words, not copied from a book or a website.
The answers given here are basic, and some learners should be expected to provide more detail.
1
Breathing: movements that make air move into or out of the lungs.
Gas exchange: the diffusion of oxygen and carbon dioxide into and out of the blood.
Respiration: chemical reactions in cells (aerobic respiration happens in mitochondria) that release
energy from glucose and other nutrients.
2
Inspired air: the air we breathe in.
Expired air: the air we breathe out.
Inspired air contains more oxygen and less carbon dioxide than expired air.
3
Red blood cells: the most numerous cells in blood, which contain haemoglobin and transport oxygen.
White blood cells: cells that help to defend the body against pathogens.
4
Trachea: the tube leading from the back of the throat towards the lungs.
Bronchus: one of two tubes branching from the trachea and taking air into both lungs.
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 2.1
Elements, mixtures and compounds
1
a
Sodium chloride is a compound.
b Water is a compound.
c
The water and sodium chloride form a solution.
d The water is a solvent.
e
2
The sodium chloride is a solute.
thermometer – temperature
ruler – distance
top pan balance – mass
measuring cylinder – volume of liquids
stop watch – time
Worksheet 2.2
Names, units and measurements
1
cm
centimetres
g
grams
s
seconds
°C
degrees Celsius
cm3
centimetres cubed
cm2
centimetres squared
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
2
cm
distance
g
mass
s
time
°C
temperature
cm3
volume
cm2
area
Worksheet 3.1
Forces and energy vocabulary
1
a
Moment
scientific meaning:the turning effect of a force/force × distance from pivot
everyday meaning: a short interval of time
b Pressure
scientific meaning: the pushing effect of a force/force per unit area/
force divided by area
everyday meaning: influence to do something/work within a tight time limit
2
Complete this crossword.
Across
2 speed
7 temperature
8 random
Down
1 graph
3 diffusion
4 moment
5 pressure
6 metres
9 depth
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 3.2
Sorting the instructions and the questions
1
a
metres per second
b newtons per metre squared/newtons per square metre
2
c
newton metres
a
speed
b pressure
c
pivot
d time
e
particles
Worksheet 4.1
Writing sentences about ecosystems
1
An ecosystem is a network of interactions between organisms and their environment.
2
A habitat is a place where an organism lives.
3
An invasive species is an introduced species that has spread widely.
Worksheet 4.2
Words and meanings
ecosystem – a network of interactions between organisms and their environment
habitat – the place where an organism lives
bioaccumulation – the build-up of substances in an organism’s body
toxic – poisonous
invasive – spreading uncontrollably
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 5.1
Words and meanings
1
1
Atomic structure
Weather
Climate
proton
rain
arid
electron
wind
tropical
nucleus
cloudy
polar
a
weather
climate
b climatology
meteorology
c
neutron
proton
d tropical climate zone
arid climate zone
Worksheet 5.2
Using the correct words
1
For example:
a
The climate in Greenland is a polar climate. It is cold and dry most of the time, with
a lot of snow and ice that does not melt during the warmer months.
b The climate in Greece is a Mediterranean climate. It is mild in the winters and the
temperature does not fall very low. In the summer it is hot and dry.
2
c
Most of northern Europe has a temperate climate with cold winters, often with snow and ice.
The summers are usually mild and not too hot.
a
The temperature yesterday was 20 °C.
b When you are wearing your safety glasses, you can pour out the acid.
c
Did you hear the instructions?
d Ernest Rutherford discovered the nucleus in the atom more than a hundred years ago.
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
3
For example:
a
Other renewable sources of energy that we can use to provide electricity are solar and tidal.
b One of the advantages of using renewable resources is that they will not run out like fossil
fuels will.
There is an advantage in the use of renewable resources to generate electricity, as they do not
produce carbon dioxide gas.
When fossil fuels are used, a lot of carbon dioxide is produced, which increases the greenhouse
effect and adds to the problem of global warming.
Renewable resources are not always available or reliable.
With wind power you can only produce electricity when the wind blows; with solar power you can
only produce electricity in the day time when the Sun shines, and with tidal power you can only
produce electricity at certain times of the day.
Some of the equipment needed to use renewable resources is expensive to set up and maintain.
The number of kilowatts of electricity generated using renewable resources is small when
compared to a power plant using fossil fuels.
Some people object to having wind farms in beautiful countryside, solar panels in fields or to
having structures that damage wildlife in estuaries.
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 6.1
Reflection and refraction vocabulary
1
a
Normal
scientific meaning: perpendicular/at right angles
everyday meaning: regular/usual/typical/average
b Plane
scientific meaning: a real or imagined level surface
everyday meaning: short form of aeroplane (different from plain);
a woodworking tool for making a wooden surface flat
2
a
When light is reflected, the angle of incidence is equal to the angle of reflection.
b In a ray diagram for a plane mirror, the angle of incidence is measured from the
direction of the incident ray to the normal.
Worksheet 6.2
Light wordsearch
1
absorbed
2
cyan
3
direction
4
filter
5
magenta
6
prism
7
reflected
8
spectrum
9
transmitted
Worksheet 6.3
Correcting the answers
1
Correct answer: refraction
2
Correct answer: stellar dust, gas, stars and solar systems/planets
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
3
Correct answer: rock
4
Correct answer: dispersion
5
Correct answer: ray diagram
Worksheet 7.1
Words and meanings
balanced diet – the food you eat each day, containing some of each nutrient and the right
amount of energy
nutrient – one of the six substances present in food that are needed by the body
hinge joint – a joint where one bone moves in one plane, like a door opening
ball-and-socket joint – a joint where one bone can move in a circular motion
growth – getting bigger
development – changes in structure and body organs that happen as you get older
Worksheet 7.2
Scrambled letters
1
carbohydrate
2
haemoglobin
3
balanced
4
protein
5
nicotine
6
monoxide
7
joint
8
antagonistic
9
contract
10 tendons
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 8.1
Selecting the correct word and spellings
1
A metal that burns with a bright light in air, and reacts vigorously in dilute acid, is said to be reactive.
2
A reaction where oxygen combines with a metal is called an oxidation reaction.
3
A chemical reaction which transfers heat to the surroundings is called an exothermic reaction.
4
If an iron gate is painted this will prevent rusting.
5
When ice melts thermal energy from the surroundings is transferred to the ice.
6
potassium
7
hydrochloric acid
8
magnesium
9
hydrogen
10 sodium hydroxide
11 sulfuric acid
12 sodium chloride
Worksheet 8.2
Writing in complete sentences and comprehension
1
Credit full sentences and a sensible description of what has to be done. For example:
They should place the citric acid in a test tube. Carefully take the temperature using a thermometer,
making sure to leave it in the test tube long enough. The thermometer should be in the acid but not
touching the side of the tube. They should record the temperature. They should add the sodium
hydrogencarbonate and allow it to react. They should take the temperature again when the reaction
finishes. They should then calculate the difference in temperature between the start and the final
temperature. If the temperature has increased, the reaction is an exothermic one. If the temperature has
decreased, the reaction is endothermic.
2
a
Iron oxide
b The properties of iron are its features, the way it behaves. Credit any correct properties,
such as that it is strong, malleable, ductile, a good conductor of heat and electricity,
shiny when new, and makes a ringing sound when hit.
c
It prevents oxygen reaching the surface of the iron so that a reaction cannot take place.
d Iron and oxygen
e
Rust is reddish brown in colour and is a flakey solid.
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 9.1
Magnetism vocabulary
1
a
poles
b attract
c
repel
d magnetic field
e
2
core
There is no single correct question for each of these; here are some examples:
a
What will happen when two like poles are brought together?
b What will happen when the current in the coil of an electromagnet increases?
c
Name three magnetic materials.
d How can you tell from a magnetic field pattern where the field is strongest?
e
What will happen when the current stops flowing in the coil?
Worksheet 9.2
Magnetism crossword
Across
2 current
5 paperclips
6 number
7 coil
8 core
9 field
Down
1 copper
2 compass
3 iron
4 electromagnet
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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CAMBRIDGE LOWER SECONDARY SCIENCE 8: LANGUAGE WORKSHEETS ANSWERS
Worksheet 9.3
Correcting the passage
There can be more than one way to correct each mistake, so an example of each is given.
A bar magnet has two poles: a north pole and a south pole. A bar magnet is surrounded by a
magnetic field. You can draw the shape of this field by using lines that point from north to south.
The lines should never cross over each other.
If you wrap a coil of wire around an iron nail, you can make an electromagnet. Current must
flow through the wire to make the nail become magnetised. When this happens, the nail will
attract paperclips.
Cambridge Lower Secondary Science 8 – Mary Jones, Diane Fellowes-Freeman and Michael Smyth © Cambridge University Press 2021
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