What role does NADP+ play in photosynthesis?

NADP+ plays a crucial role as an electron acceptor in photosynthesis, specifically during the light-dependent reactions. When light energy is captured by chlorophyll in the thylakoid membranes, water molecules are split in a process known as photolysis, resulting in the release of oxygen and the generation of electrons. These high-energy electrons are transferred through the electron transport chain, where they gradually lose energy and help pump protons into the thylakoid lumen, creating a proton gradient.

At the end of this electron transport chain, NADP+ accepts the electrons along with protons to form NADPH, a reduced form of NADP+. This conversion is essential because NADPH acts as a carrier of reducing power, providing the electrons needed for the Calvin cycle, where carbon dioxide is fixed into glucose.

This versatile role of NADP+ as an electron acceptor is a key part of the photosynthetic process, enabling the transformation of light energy into chemical energy stored in organic molecules.