The photograph shows a locust - Edexcel - GCSE Biology - Question 5 - 2017 - Paper 1
Question 5
The photograph shows a locust.
(a) (i) Locusts feed on maize plants and locusts are eaten by lizards. Lizards are eaten by snakes. Complete a food chain for these o... show full transcript
Worked Solution & Example Answer:The photograph shows a locust - Edexcel - GCSE Biology - Question 5 - 2017 - Paper 1
Step 1
Complete a food chain for these organisms.
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Answer
The food chain can be represented as:
Maize (plants) → Locusts → Lizards → Snakes
This denotes that maize plants provide energy to the locusts, locusts are preyed upon by lizards, and lizards are consumed by snakes.
Step 2
Complete the sentence by putting a cross (X) in the box next to your answer.
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Answer
Maize plants get energy to grow from the
D sunlight
This indicates that maize plants, being autotrophic, utilize sunlight for photosynthesis to produce their own food.
Step 3
Calculate how much of the maize plant biomass is passed on to the locusts.
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Answer
To find out how much biomass is passed on to the locusts, calculate 8% of 8800g:
total ext{biomass} = 8800g imes rac{8}{100} = 704g
Thus, 704g of biomass is transferred to the locusts.
Step 4
State one reason why only 8% of the biomass from the maize plants is passed on to the locusts.
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Answer
One reason why only 8% of the biomass is passed on to the locusts is due to energy loss at each trophic level. Energy is lost in the form of heat during metabolic processes, as well as through excretion and other biological functions, resulting in only a fraction of the energy being transferred.
