Coenzymes coenzyme Q

Coenzyme Q is capable of accepting either one or two electrons to form either a semiquinone or hydroquinone form. Figure 11-4 shows the quinone, semiquinone, and hydroquinone forms of the coenzyme. Coenzyme Q is not bound to a protein instead it is a mobile electron carrier and can float within the inner membrane, where it can transfer electrons from Complex I and Complex II to Complex 111. 

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