* ATP (Adenosine triphosphate): This is the energy currency of the cell.
* NADPH (Nicotinamide adenine dinucleotide phosphate): This is a reducing agent that carries high-energy electrons.
These molecules are produced by the following processes:
* ATP synthesis: Light energy is used to pump protons (H+) across the thylakoid membrane, creating a proton gradient. This gradient is used by ATP synthase to generate ATP from ADP and inorganic phosphate.
* NADPH production: Light energy is used to excite electrons in chlorophyll. These excited electrons are passed along an electron transport chain, ultimately reducing NADP+ to NADPH.
Key Points:
* The light-dependent reactions occur in the thylakoid membranes of chloroplasts.
* Light energy is essential for these reactions.
* ATP and NADPH are essential for the Calvin cycle (light-independent reactions), which produces glucose.
