Chemistry of photosynthesis

The chemistry of photosynthesis is the set of chemical reactions through which plants, algae, and certain bacteria convert light energy into chemical energy stored in glucose and other organic compounds.

The process unfolds in two main stages. The light-dependent reactions, occurring in the thylakoid membranes of chloroplasts, harness photons to split water molecules, releasing oxygen and generating energy carriers: ATP and NADPH. These reactions exploit the behavior of chlorophyll and other pigments that absorb specific wavelengths of light.

The light-independent reactions (or Calvin cycle), occurring in the stroma, use that ATP and NADPH to fix carbon dioxide into three-carbon molecules, eventually building glucose through a series of enzyme-catalyzed steps involving RuBP and 3-PG.

Together, these reactions represent one of nature's most elegant energy transformations—the engine powering nearly all life on Earth. Understanding photosynthesis at the molecular level reveals how electron transport, proton gradients, and enzymatic catalysis orchestrate the capture of starlight itself.

Related

Photosynthesis, Cellular respiration, Biochemistry, Photosystem, Electron transport