### B1.5 Energy and biomass in food chains

```B1.5 Energy and biomass in food chains
GCSE items that can be used to define successful outcomes
for peer and self assessment activities
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Assessment of practical work
Using Exam pro items to support successful outcomes
Students will be able to test their progress against learning
outcomes using questions taken from past AQA GCSE
examinations.
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B1.5 Energy and biomass in food chains June 2012 BL1FP
Version 2.0
B1.5 Energy and biomass in food chains June 2012 BL1FP
Version 2.0
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Version 2.0
B1.5 Energy and biomass in food chains June 2012 Mark Scheme
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B1.5 Energy and biomass in food chains June 2012 BL1HP
Students investigated a food chain in a garden.
The students found 650 aphids feeding on one bean plant.
Five ladybirds were feeding on the aphids.
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B1.5 Energy and biomass in food chains June 2012 BL1HP
(a) (i) Draw a pyramid of biomass for this food chain.
Label the pyramid.
(2 marks)
(a) (ii) The biomass in the five ladybirds is less than the biomass
in
the bean plant. Give two reasons why.
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(2 marks)
(b) The carbon in dead bean plants is returned to the
atmosphere
via the carbon cycle.
Describe this part of the carbon cycle.
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(4 marks)
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Version 2.0
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B1.5 Energy and biomass in food chains June 2012 Mark Scheme
Mark scheme
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B1.5 Energy and biomass in food chains June 2012 BL1HP
The diagram shows the annual flow of energy through a habitat.
The figures are in kJ m-2
8 (a) (i) Calculate the percentage of the energy in sunlight that
was transferred into energy in the green plants.
(2 marks)
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B1.5 Energy and biomass in food chains June 2012 BL1HP
(a) (ii) Suggest reasons why the percentage energy transfer you
calculated in part (a)(i) was so low.
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(2 marks)
(b) Compare the amount of energy transferred to the insecteating birds with the amount transferred to the predatory
birds. Suggest explanations for the difference in the amount of
energy transferred to the two types of bird.
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(3 marks)
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