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Photosynthesis takes place inside organelles called . The process of photosynthesis can be broken into two major parts: the light- reactions and the light- reactions.

Light Dependent Reactions

lightrxn.gifThe light-dependent reactions take place inside the chloroplasts in stacks of called . Light from the is absorbed by plant pigments such as . The enegy from sunlight is used to split molecules of . The gas is produced and returned to the atmosphere. The remaining H+ ions and (e-'s) are used to recharge the carrying molecules needed for the light-independent reactions:

ADP is recharged to become
NADP+ is recharged to become

Light Independent Reactions

cycle.gifThe light-independent phase is sometimes called the "" phase because it does not rely directly upon sunlight. The light independent reactions take place in the fluid of the chloroplast called the . The energy carrying molecules ATP and NADPH, which were recharged in the light dependent reactions, are used to incorporate the gas into molecules that make the sugar called . This sugar has the
formula 6126. This set of reactions, powered by ATP and NADPH, is collectively called the cycle.

Overall Reaction

The overall reaction for photosynthesis is sometimes written this way:

carbon dioxide + + oxygen