Which part of photosynthesis is primarily responsible for the production of sugars?

• A. Calvin Cycle (light-independent reactions)
• B. Light-dependent reactions
• C. Electron transport chain
• D. Photolysis of water

Answer: (A)

Verified step by step guidance

1. Understand that photosynthesis consists of two main stages: the light-dependent reactions and the light-independent reactions (Calvin Cycle). The light-dependent reactions occur in the thylakoid membranes and produce ATP and NADPH, which are used in the Calvin Cycle.
2. Recognize that the Calvin Cycle is the stage of photosynthesis responsible for the production of sugars. It occurs in the stroma of the chloroplast and does not require light directly, hence it is called light-independent reactions.
3. Learn that the Calvin Cycle uses ATP and NADPH generated during the light-dependent reactions to convert carbon dioxide (CO₂) into glucose through a series of enzymatic steps.
4. Understand the key steps of the Calvin Cycle: carbon fixation (where CO₂ is attached to ribulose-1,5-bisphosphate), reduction phase (where 3-phosphoglycerate is converted into glyceraldehyde-3-phosphate), and regeneration of ribulose-1,5-bisphosphate.
5. Note that while other processes like the electron transport chain and photolysis of water are essential for generating the energy and reducing power needed for the Calvin Cycle, they are not directly responsible for sugar production.