Photosystem II :
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1.) Photosystem II
Photosystem II is one of two photo-reactive complexes in the photosynthetic electron transport system. It is the only complex capable of producing breathable oxygen. This section will give an overview of the molecules and structures that make up this complex. Clicking on each of the
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The Photosystem II reaction center is composed of many different proteins and pigment molecules.
At the heart of the reaction center is a special pair of chlorophyll molecules known as P680, that donate electrons to the photosynthetic electron transport system. Along with two pheophytin molecules and two plastoquinones known as Qa and Qb.
The P680 reaction center is bound within the the D2 and D1 proteins.
Located at the luminal side of the Photosystem II complex is the oxygen-evolving complex. Water molecules are split here to provide electrons that will reduce P680.
Surrounding the Photosystem II reaction center is a light absorbing antenna complex of cholorophyll molecules known as the light harvesting complex (LHC).