Photoinhibition is a reduction in a plant's (or other photosynthetic organism's) capacity for photosynthesis caused by exposure to strong light (above the saturation point). Photoinhibition isn't caused by high light per se, but rather absorption of too much light energy compared with the photosynthetic capacity, for example any excess energy that the photosystem can't handle is damaging. Too much light energy affects (photosystem II (P680)) more than photosystem I (PSI), and it has been hypothe… (More on Photoinhibition)