What's the difference between the light dependent and independent reactions?

These two sets of reactions are very different yet equally important in the process of photosynthesis.

The light dependent reactions consist of chlorophyll molecules absorbing a photon (hence light dependent) that causes electrons in the molecule to be raised to a higher energy level and pass down the electron transport chain, which makes energy available to produce ATP. The loss of electrons causes the splitting of water (known as photolysis) into 2H+, 1/2 Oand electrons, which replace those lost by the chlorophyll. The electrons that flowed through the electron transport chain combine with the hydrogen ions from water and NADP to form NADPH + H+. These reactions occur on the thylakoid membranes.

The light independent reactions consist of the Calvin cycle where CO2 is fixed by combining with RuBP to form 2GP, and then uses the products of the light dependent reactions to form GALP, which can be converted into many different products.

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