Process of Photosynthesis

 Photosynthesis is an oxidation-reduction process in which water is oxidized and CO2 is reduced to

carbohydrates and water, and O2 molecules are by-products. The reduction of CO2 to carbohydrate level needs

assimilatory powers such as ATP and NADPH2. Reduction of CO2 occurs in dark (light-independent) but the

production of assimilatory powers takes place in the presence of light and the process is light-dependent.

Thus, Photosynthesis consists of two phases :

1. Light-dependent phase (light reaction or Hill reaction) and

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2. Light-independent phase (dark reaction or Blackman’s reaction).

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