CAIE A Level Biology 9700 · Photosynthesis
In photosynthesis, the Calvin cycle uses ATP and reduced NADP from the light-dependent stage to fix carbon dioxide. The triose phosphate (TP) produced can be used to synthesise various organic compounds. Explain how the Calvin cycle provides intermediates for the synthesis of amino acids and carbohydrates, and why the light-dependent stage is necessary for these processes.
6 marks, so the mark scheme is looking for about 6 separate creditworthy points. Making the same point twice in different words earns it once.
Explain means: Give the reasons or the mechanism: why or how something happens. Link each point to the next with because, so or which means. A list of facts with no links usually loses the reasoning marks.
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