Pigment Systems I and II of Photosynthesis

Both pigment systems or collectives have this in common that, in both of them, many chlorophyll molecules are combined with accessory pigments to form a unit. Of pigment I it is known with certainty and of pigment II with some probability that only one of the many chlorophyll molecules can be excited by a quantum of incident light. 

Pigment system IL Much less is known about pigment system II than about pigment system I. The active chlorophyll in this case has not been unambiguously identified. It is assumed that the principle of the trapping center applies also in the case of pigment system II. The active 

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