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Question
The reactions of photosynthesis make up a biochemical pathway.
Explain how the biochemical pathway of photosynthesis recycles many of its own reactions and identify the recycled reactants.
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Solution
Light reactions use light to synthesize ATP and NADPH2. The Calvin cycle uses these reactants to produce sugar from CO2 molecules.
This cycle then produces NAP + ADP + Pi which is used in the light reaction with H2O molecules to produce ATP and NADPH2 again.
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