This document provides an authentic learning task in Life Sciences for grade 10 students on the topic of environmental studies and ecology. The task aims to help students draw food chains and food webs, explain biological cycles, distinguish between biotic and abiotic factors, and explain the impact of humans on the environment. It contains 6 multiple choice and short answer questions addressing these concepts and asks students to interpret food webs and diagrams, explain ecosystem dynamics, and analyze how human activities and environmental changes can impact ecosystems.

1. Authentic
LearningTask
Life Sciences Grade 10: Environmental Studies- Ecology

2. By the end of this task, you should be able to
• Draw food chains and food webs.
• Name and explain how biological cycles work.
• Distinguish between Biotic and Abiotic factors.
• Explain the impact humans have on the environment.
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3. Question 1
As part of an ecological study, the biomass of organisms
in a community was estimated
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a.) Give the letter that represents the producers in this
community. (1)
b.) From this data draw a food chain of the organisms in the
correct order using all the letters provided . (4)

4. Question 2
The diagram below shows the feeding relationships in a
coral reef in the Caribbean.
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a.) Use the diagram to explain why a coral reef can be described as an
ecosystem. (2)
b.) Explain why the sea stars are both secondary and tertiary consumers.
(2)
c.) Name another abiotic factor, besides those listed that will play a role in
this ecosystem. (1)
d.) StateTWO ways in which human activities may affect coral reef
ecosystems, either directly or indirectly. (2)
e.) Explain how conservation of the coral reefs may benefit the local
communities. (2)
f.)The parrot fish, shown in the diagram, became infected by a virus which
drastically reduced their numbers. Explain two effects that this might
have on other organisms in the ecosystem. (4)

6. Question 3
Name and explain how these biological cycles work (12)
a) b)

7. c)
d)
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8. Question 4
a) What are Human Influences on the Environment? (5)
b) A multi-national mining corporation is seeking the rights mine coal in the
Kruger National Park.What argument can you make in support of this
proposal and in opposition to the proposal? (10)
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9. Question 5
In an investigation soil samples with different pH values were taken to determine in which pH
range different soil animals prefer to live.
Study the following graph, which shows the range of pH within which each of four soil animals (A
to D) is found.
a.)Which species (A to D):
i. Occurs over the widest range of pH
conditions? Explain your answer (3)
ii. Can survive in pH conditions below
4 (1)
iii. Appears to be least tolerant of
acidic conditions (1)
b.) Except for pH, name ONE other
soil factor that might influence
where soil animals would prefer to
live. (1)
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10. Question 6
a) Biotic Factors
List the biotic factors according to their
categories.
Physical Factors Physiographic Factors Edaphic Factors (Soil)
e.g. Light intensity e.g. Aspect •e.g. ph.
Abiotic Factors: Fill in the blank spaces
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