Plants have mechanisms that protect against adverse effects of strong light. The most studied biochemical protective mechanism is non-photochemical quenching of excitation energy. Visible-light-induced photoinhibition is ~25% faster in an Arabidopsis thaliana mutant lacking non-photochemical quenching than in the wild type. It is also apparent that turning or folding of leaves, as occurs, e.g., in Oxalis species in response to exposure to high light, protects against photoinhibition.