Light-driven electron transport reaction. Absolutely dependent upon Chlorophylls. Dark electron transport reactions follow initial charge separation event. No involvement of light. Very similar to respiration.
Light absorption leads to electron transfer from donor chlorophyll to an acceptor.
Charge separation occurs. Unique to cyanobacteria. Only function as antenna proteins. Very high absorbtivity for visible light. Differ in organization from antenna proteins by having appropriate electron acceptors near a pair of chlorophylls.