Biology 9700 · AS & A Level · Photosynthesis as an energy transfer process

Photosynthesis as an energy transfer process — practice question

Photosynthesis is the process of energy transfer in chloroplasts. Fig. 5.1 illustrates several biochemical events taking place in a chloroplast during the light-dependent stage of photosynthesis. Photosystems I and II (PSI and PSII) together with some associated proteins in the thylakoid membrane are shown.
(a(i))[2]

A and B are regions within the chloroplast. Name areas A and B.

(a(ii))[2]

The proteins labelled C, PSI and the protein labelled E take part in a particular biochemical process during the light-dependent stage of photosynthesis. Name this biochemical process and the protein labelled E.

(a(iii))[3]

Product D is used in the Calvin cycle. Identify product D and describe its particular role in the Calvin cycle.

(b(i))[3]

Limiting factors influence the rate of photosynthesis. Describe and suggest how the results for tropical forest, temperate forest and snow forest in Fig. 5.2 demonstrate the effect of limiting factors on photosynthesis.

(b(ii))[3]

Suggest reasons why grasslands and desert habitats have a lower rate of energy transfer by photosynthesis than forests.

(ii)[3]

Suggest why grasslands and desert habitats transfer energy by photosynthesis at a lower rate than forests.

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