Here's a breakdown:
* Photosynthesis: Photosynthesis is divided into two main stages: the light-dependent reactions and the Calvin cycle (carbon-fixation).
* Light-dependent reactions: These reactions occur in the thylakoid membranes of chloroplasts. During these reactions, light energy is captured and used to generate ATP (energy currency) and NADPH.
* NADPH: This is a reduced form of NADP+ (nicotinamide adenine dinucleotide phosphate) and carries high-energy electrons.
* Calvin Cycle: The Calvin cycle occurs in the stroma of chloroplasts. It uses the ATP and NADPH generated in the light-dependent reactions to convert carbon dioxide into sugars (glucose).
* Hydrogen: NADPH provides the hydrogen atoms (specifically, electrons and protons) needed to reduce carbon dioxide into sugars during the Calvin cycle.
In short: NADPH acts as a carrier of reducing power, providing the necessary hydrogen to power the carbon-fixation process.
