What is Photosystem II?
{{Redirect|PSII|the PS2|PlayStation 2}} [[Image:PhotosystemII.PNG|right|thumb|350px|Cyanobacteria photosystem II]] '''Photosystem II''' is a large [[protein]] complex. It is the first protein complex in the [[light-dependent reactions]] of oxygenic [[photosynthesis]]. The complex is in the [[thylakoid membrane]] of [[plants]], [[algae]], and [[cyanobacteria]]. In the photosystem, [[enzyme]]s capture [[photons]] of light to energize [[electrons]]. The electrons are then transferred by [[coenzyme]]s and [[Cofactor (biochemistry)|cofactors]]. The energized electrons are replaced by [[oxidation|oxidizing]] water to form [[hydrogen ion]]s and molecular [[oxygen]]. By replenishing lost electrons with electrons from the [[Photodissociation|splitting of water]], photosystem II provides the electrons for [[photosynthesis]] to occur.<ref>Nowicka, Beatrycze & Kruk, Jerzy 2010. Occurrence, biosynthesis and function of isoprenoid quinones. ''Biochimica et Biophysica Acta'' (BBA) - Bioenergetics. 1797 (9): 1587–1605.</ref> == References == {{reflist}} [[Category:Photosynthesis]] [[Category:Plant physiology]]