In oxygenic photosynthesis in plants, what is the second major stage after the light-dependent reactions?

• A. The Calvin cycle (light-independent reactions) in the stroma that fixes $C_{O}2$ into sugars
• B. Electron transport in the thylakoid membrane to generate a proton gradient for ATP synthesis
• C. Photolysis of water at photosystem II to release $O_2$ and electrons
• D. Glycolysis in the cytosol to break down glucose into pyruvate

Answer: (A)

Verified step by step guidance

1. Identify the two major stages of oxygenic photosynthesis: the light-dependent reactions and the light-independent reactions.
2. Understand that the light-dependent reactions occur in the thylakoid membranes and involve capturing light energy to produce ATP and NADPH.
3. Recognize that the second major stage, following the light-dependent reactions, is the Calvin cycle, also known as the light-independent reactions.
4. Know that the Calvin cycle takes place in the stroma of the chloroplast and uses ATP and NADPH from the light-dependent reactions to fix carbon dioxide (CO\_2) into organic molecules like sugars.
5. Distinguish the Calvin cycle from other processes such as electron transport, photolysis, and glycolysis, which either occur in different locations or serve different functions.