LightReaction of photosynthesis z scheme.pptx

light reaction in thylakoid

1. Overview of Light Reaction Occurs in the thylakoid membranes of chloroplasts Requires light energy (photons) to initiate Converts solar energy into chemical energy (ATP and NADPH) Water is split (photolysis), releasing O₂ as a by-product ATP and NADPH power the Calvin Cycle

2. Photosynthetic Electron Transport Chain Electrons move through a chain of redox reactions Starts at PSII and ends at NADP⁺ reductase Electrons move: PSII → PQ → Cyt b6f → PC → PSI → Fd → NADP⁺ Energy released is used to pump protons into thylakoid lumen Proton gradient drives ATP synthesis via ATP synthase