The capture of light energy and its transformation into chemical energy in the form of ATP and NADPH

During the light dependent phase of photosynthesis, light energy from the sun is harvested by special pigments on the thylakoid membranes of the chloroplasts. Chlorophyll (specifically chlorophyll a) is the most important of these pigments. The pigments are not arranged haphazardly on the surface of the chloroplast but in specific aggregates known as photosystems. The photosystems play a central role in the light dependent phase of photosynthesis. In the light dependent reaction of photosynthesis, an energy-rich electron from a special chlorophyll molecule in a photosystem is passed along a chain of molecules known as the electron transfer system in a process called photophosphorylation. The energy lost by the electron, as it moves along the chain, is used to make ATP. Read on to find out how this works !

But first find out more about photosystems

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