The function of sunlight in photosynthesis is to A) reduce NADPH to NADP. B) fix O₂ in the Calvin cycle. C) excite electrons in chlorophyll. D) combine carbon dioxide and water to form ATP and NADPH.

Question

Quizplus · Accepted Answer

Sunlight is absorbed by chlorophyll within the chloroplasts of plant cells, exciting the electrons and starting the process of photosynthesis.

Answer: B 
 The fixation of carbon dioxide in the Calvin cycle is driven by the ATP and NADPH produced in the light-dependent reactions, which are themselves driven by the absorption of light by chlorophyll.

Therefore, neither A nor D are correct choices.

The Function of Sunlight in Photosynthesis Is to