Worksheet on Energy and the Ecosystem
Biology Worksheet
Chapter XXI (Ecology)
Presidency International School
1. Which type of organism depends directly on light energy for its nutrition?
A carnivore
B decomposer
C herbivore
D producer 5090/11/M/J/16
2. The diagram shows a pyramid of biomass for the food chain: grass → zebra → lion.
Which process causes loss of biomass from this food chain?
A digestion
B growth
C photosynthesis
D respiration 5090/01/M/J/03
3. The diagram shows a food web.
Which levels represent carnivores?
A P and Q
B P and R
C Q and R
D R and S 5090/01/M/J/03
4. Which diagram shows part of the energy flow in an ecosystem?
5090/01/O/N/07
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Worksheet on Energy and the Ecosystem
5. The diagram below shows part of a pond food web.
How many primary consumers are shown in this food web?
A 1 B 2 C 3 D 4 5090/01/O/N/09
6. A single plant provides food for many herbivores. The herbivores supply food for a few carnivores.
Which pyramid of numbers and which pyramid of biomass show this information?
pyramid of numbers pyramid of biomass
A W Y
B W Z
C X Y
D X Z
5090/01/M/J/04
7. The diagram shows a food chain.
tree → mice → cats → fleas
What is the shape of the pyramid of numbers for this food chain?
5090/11/M/J/17
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Worksheet on Energy and the Ecosystem
8. The diagram shows a food chain.
grass → rabbit → fox → flea
Which pyramid of numbers matches this food chain?
5090/11/O/N/17
9. In the diagram, arrows represent the movements of carbon compounds in the carbon cycle. The circles
represent carbon compounds in animals, decomposers, plants and the atmosphere.
What is represented by each circle?
1 2 3 4
A animals decomposers plants atmosphere
B atmosphere plants decomposers animals
C decomposers animals atmosphere plants
D plants atmosphere animals decomposers
5090/01/O/N/04
10. The diagram shows changes in the appearance of a leaf over a period of time, as it lies on the damp
ground.
Which type of organism is most likely to cause these changes?
A carnivore
B decomposer
C herbivore
D producer 5090/11/O/N/15
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Worksheet on Energy and the Ecosystem
11. The diagram shows part of the carbon cycle.
What are the processes X and Y?
X Y
A Photosynthesis decomposition
B photosynthesis excretion
C respiration photosynthesis
D respiration respiration
5090/11/M/J/16
12. The diagram shows the carbon cycle.
What are processes P, Q, and R?
P Q R
A Photosynthesis photosynthesis respiration
B respiration respiration photosynthesis
C photosynthesis respiration photosynthesis
D respiration photosynthesis respiration
5090/01/M/J/05
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Worksheet on Energy and the Ecosystem
13. A sparrow hawk eats small birds that feed on caterpillars. Caterpillars feed on plant leaves.
Which diagram shows the pyramid of biomass for this food chain?
5090/01/M/J/06
14. The diagram shows a river that flows down from the mountains to the sea. Trees are cut down and
removed from the shaded area.
After a rainstorm, what is the effect on the nitrate ion content at X and at Y?
nitrate ion content at X nitrate ion content at Y
A increases increases
B increases decreases
C decreases increases
D decreases decreases
5090/11/M/J/16
15. How is malaria usually transmitted from human to human?
A by a bacterium
B by a mosquito
C by a pathogen
D by contaminated water 5090/11/M/J/16
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Worksheet on Energy and the Ecosystem
16. The diagram shows a food web from an ecosystem.
If the population of insects decreases, which other population will decrease the most?
A badgers
B lizards
C sagebrush
D squirrels 5090/01/M/J/08
17. The diagram shows a food web in woodland.
In this food web, the beetles are
A carnivore
B decomposer
C herbivore
D producer 5090/12/M/J/10
18. The diagram shows a pyramid of biomass.
Which percentage of biomass is passed from the primary consumer to the secondary consumer?
A 1% B 10% C 20% D 50% 5090/12/O/N/16
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Worksheet on Energy and the Ecosystem
19. The diagram shows part of a food web.
How many herbivores are shown?
A 3 B 4 C 5 D 6 5090/11/M/J/11
20. The diagram shows some structures, Q, on the roots of a bean plant.
Which chemical change fixes nitrogen in these structures?
A ammonium salts to nitrates
B nitrogen to ammonium salts
C proteins to amino acids
D proteins to ammonium salts 5090/12/M/J/16
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Worksheet on Energy and the Ecosystem
21. The diagram shows a food web in a pond.
Which of the organisms is a carnivore, which is a herbivore and which is a producer?
carnivore herbivore producer
A 3 8 1
B 7 6 1
C 8 3 4
D 5 2 4
5090/11/M/J/12
22. The diagram shows the carbon cycle.
During which stage in the cycle is oxygen excreted by living organisms?
5090/12/O/N/17
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Worksheet on Energy and the Ecosystem
23. Insects feed on a tree’s leaves. The insects are eaten by small birds that are the prey of larger birds.
Which pyramid of numbers illustrates this food chain?
5090/12/M/J/17
24. The diagram shows a pyramid of numbers.
Which food chain is represented by this pyramid of numbers?
A grass → antelope → lion → flea
B mahogany tree → caterpillar → finch → hawk
C microscopic plants → microscopic animals → small fish → shark
D pond plant → snail → large beetle → fish 5090/11/O/N/16
25. The diagram shows part of the nitrogen cycle.
Which stages involve bacteria?
A P, Q and T B P, R and S C Q, S and T D R, S and T 5090/01/O/N/07
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Worksheet on Energy and the Ecosystem
26. The diagram shows part of the nitrogen cycle.
Which stage depends on nitrifying bacteria?
5090/01/O/N/09
27. In a fish tank, bacteria recycle animal waste for plants to use.
The diagram shows some of the stages in this process.
What are compounds 1, 2 and 3?
1 2 3
A ammonia nitrates nitrites
B ammonia nitrites nitrates
C nitrates ammonia nitrites
D nitrites ammonia nitrates
5090/11/O/N/17
28. Which row shows the malarial parasite and the vector involved in its transmission?
parasite vector
A female mosquito human
B human male mosquito
C malarial pathogen female mosquito
D male mosquito malarial pathogen
5090/11/M/J/17
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Worksheet on Energy and the Ecosystem
29. The diagram shows part of the nitrogen cycle.
Which stages depend on the action of bacteria?
A 1 and 2
B 2 and 3
C 3 and 4
D 4 and 1 5090/01/M/J/06
30. The diagram shows a building in a tropical country.
What would be the most effective way of preventing a person who sleeps in the building from catching
malaria?
A Divert the stream away from the house since mosquitoes breed in water.
B Move the latrines further away from the building since sewage attracts mosquitoes.
C Put netting over the door and window to prevent the entry of mosquitoes.
D Spray insecticide on the maize crop to kill mosquitoes. 5090/12/O/N/13
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