AP BIOLOGY

Detailed explanation-1: -Photosystem I reduces NADP. Plastocyanin that has been reduced by the cyt-b6/f complex diffuses through the lumen of the thylakoids, binds to a positively charged binding site of PS I, transfers its electron, and the resulting oxidized form diffuses back to the cyt-b6/f complex (Fig. 3.31).

Detailed explanation-2: -Photosystem I (PSI) of photosynthesis (Fig. 1) provides energy to reduce NADP to NADPH, which is required for carbon fixation and other synthetic processes.

Detailed explanation-3: -The electrons travel through the chloroplast electron transport chain to photosystem I (PSI), which reduces NADP+ to NADPH (Figure 3).

Detailed explanation-4: -The process by which NADP+ is reduced to NADPH. The light reactions of photosynthesis use energy from photons to generate high-energy electrons. These electrons are used directly to reduce NADP+ to NADPH. NADPH is a relatively stable molecule and can pass on its hydrogen atom to other molecules in chemical reactions.

Detailed explanation-5: -The reaction center chlorophyll of photosystem I transfers its excited electrons through a series of carriers to ferrodoxin, a small protein on the stromal side of the thylakoid membrane. The enzyme NADP reductase then transfers electrons from ferrodoxin to NADP+, generating NADPH.