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Related to light reaction: dark reaction
Any of the chemical reactions that take place as part of the first stage of photosynthesis and require the presence of light, by which energy captured from light is converted to chemical energy in the form of ATP.
That stage of photosynthesis in which photons are captured by cells and used to supply the energy needed to synthesize carbohydrates. Chlorophyll is the light-trapping molecule of most plants. Bacteriochlorophyll is a related compound used by bacteria to capture the energy supplied by light.