AP BIOLOGY

Detailed explanation-1: -The light-dependent reactions use light energy to make two molecules needed for the next stage of photosynthesis: the energy storage molecule ATP and the reduced electron carrier NADPH. In plants, the light reactions take place in the thylakoid membranes of organelles called chloroplasts.

Detailed explanation-2: -ATP and NADPH produced by the light-dependent reactions of the photosystems are used by the Calvin cycle in the stroma of the chloroplast. Molecules of CO2 gas are fixed into molecules of 3-phosphoglycerate in a reaction catalyzed by the enzyme Rubisco.

Detailed explanation-3: -The light-dependent reactions convert light energy into chemical energy, producing ATP and NADPH. The light-dependent reactions can be summarized as follows: 12 H2O + 12 NADP+ + 18 ADP + 18 Pi + light and chlorophyll yields 6 O2 + 12 NADPH + 18 ATP.

Detailed explanation-4: -Generating Another Energy Carrier: NADPH As the electron from the electron transport chain arrives at photosystem I, it is re-energized with another photon captured by chlorophyll. The energy from this electron drives the formation of NADPH from NADP+ and a hydrogen ion (H+).

Detailed explanation-5: -2: The light-independent reactions (Calvin cycle) has three stages. In stage 1, the enzyme RuBisCO adds carbon dioxide to RuBP, which immediately splits, producing two three-carbon 3-PGA molecules. In stage 2, two NADPH and two ATP are used to reduce 3-PGA to GA3P.