Question

What is the purpose of the ATP and NADPH produced in the light reactions of photosynthesis?

A. to transfer light energy to excited electrons
B. to stop the electron transport chain
C. to act as carrier proteins in inner mitochondrial membranes
D. to transfer energy to compounds forming three-carbon sugars

Answer 1

Answer: D. to transfer energy to compounds forming three-carbon sugars

Explanation: ATP and NADPH are produced in the light reactions by

when energy absorbed from the sun is conserved as ATP and NADPH. ATP and NADPH generated in the light reactions of photosynthesis are used to synthesize carbohydrates from carbon dioxide and water. The ATP and NADPH are used to reduce CO2 to triose phosphate which can be used to produce glucose. Green plants contain unique enzymatic machinery in their Chloroplasts which catalyzes the conversion of carbon dioxide to simple organic compounds in a process known as CO2 assimilation or carbon fixation. In this carbon fixation reactions, ATP and NADPH is used to drive the incorporation of carbon dioxide into ribulose 1,5-bisphosphate to produce glyceraldehyde 3-phosphate (a 3-carbon sugar) in a series of enzyme catalyzed reactions.