Stage 2 photosynthesis involves:

• A. Chemical energy used to reduce CO2 to carbohydrate
• B. Water is oxidized to O2 and energy is released
• C. CO2 released as waste
• D. Light energy absorbed by pigments

Answer: (A)

Stage 2 photosynthesis is the Calvin cycle, where CO2 is fixed and reduced to carbohydrate using chemical energy stored as ATP and NADPH produced during the light-dependent reactions. This stage relies on those energy carriers from Stage 1, not directly on light itself, to drive carbon fixation and sugar synthesis. Water oxidation and O2 release occur in Stage 1, light energy absorption by pigments happens in Stage 1, and CO2 is used (not released) in Stage 2.