Grade 8
Biology
Term 3 Revision Worksheet
1
Water travels through plants.
Look at the list of parts of a plant.
A leaf xylem
B stem xylem
C stoma on the surface of leaf
D root hair cell
E root xylem
Write down parts A to E in the correct order to show the pathway of water through a plant.
One has been done for you.
B
[2]
2
The diagram shows the pathway of water from the roots to a leaf in a flowering plant.
absorption of water
through the roots
transport of water
up the stem
loss of water from
the surface of the leaf
(a) (i) Name the cells in the root that absorb water from the soil.
[1]
(ii) Name the tube in the stem that transports water up the flowering plant.
[1]
(iii) Name the process that causes the loss of water from the surface of the leaf.
[1]
3
Look at the diagram of part of the cross-section of a plant leaf.
upper layer
palisade layer
vein
spongy layer
lower layer
stoma
(a) The palisade layer contains many chloroplasts.
(i) What process happens inside chloroplasts?
[1]
(ii) Name two gases exchanged through the stoma.
1
2
[2]
(b)
Chloroplasts contain chlorophyll. Write down it's functio
[1]
(c) What are the reactants in photosynthesis ?
[1]
4
This question is about the carbon cycle and climate change.
(a) Complete the carbon cycle diagram.
Choose words from the list.
combustion
decomposition
photosynthesis
feeding
respiration
sunlight
carbon dioxide in
the atmosphere
..........................................................
..........................................................
..........................................................
fossil
fuel
power
station
..........................................................
..........................................................
dead plants
and animals
fossil fuels
[3]
b) Describe what happens during decomposition.
[1]
5
The diagram shows the genetic material inside an animal cell.
A
B
D
C
E
Look at parts A, B, C, D and E.
(a) Circle the letter that shows a chromosome.
A
B
C
D
E
[1]
(b) Circle the letter that controls a single characteristic such as eye colour.
A
B
C
D
(c) Write down the name of the chemical that is in a chromosome.
E
[1]
6
The diagram shows how the appearance of a deer population changes over time.
Q
The deer move to
a colder climate.
R
In the colder
climate, some deer
survive better than
others.
P
This population of deer
live in a warm climate.
S
The deer that survive
reproduce.
(a) Look at the diagram.
The deer show variation.
Describe one example of variation shown in the diagram.
[1]
The appearance of the deer population changes over time from P to S.
The theory of natural selection explains this change in appearance.
Match each statement about natural selection to the correct letter in the diagram.
You may use each letter once, more than once or not at all.
statement about natural selection
Some adaptations give advantages in one environment and not in another.
Genes controlling features which help survival pass into offspring.
Individuals with adaptations less advantageous to the environment die before
they reproduce.
letter
7
This question is about the population of cheetahs and sea turtles.
(a) Look at the graph showing the change in the number of cheetahs since 1900.
120 000
100 000
80 000
number
of cheetahs
60 000
40 000
20 000
0
1900
1940
1980
2020
2060
3000
year
(i) Describe the change in the number of cheetahs between 1900 and 2020.
[1]
(ii) Draw an extension to the line of best fit to the x-axis.
Estimate the year when the cheetah becomes extinct.
year
[2]
(iii) The change in the number of cheetahs may be due to natural selection.
Describe the theory of natural selection.
[2]