MUSCLE PHYSIOLOGY

Detailed explanation-1: -FAD, in its fully oxidized form, or quinone form, accepts two electrons and two protons to become FADH2 (hydroquinone form). The semiquinone (FADH·) can be formed by either reduction of FAD or oxidation of FADH2 by accepting or donating one electron and one proton, respectively.

Detailed explanation-2: -Redox reactions require that electrons can be transferred or removed to either reduce or oxidize a particular substrate or molecule. Therefore, we need intermediates capable of undergoing electron transfer. These are the coenzymes NAD/NADH and FAD/FADH2.

Detailed explanation-3: -Flavin adenine dinucleotide (FAD) is an important redox cofactor involved in many reactions in metabolism. The fully oxidized form, FAD, is converted to the reduced form, FADH2 by receiving two electrons and two protons.

Detailed explanation-4: -FAD is the oxidized (quinone) form, which is reduced to FADH2 (hydroquinone form) by accepting two electrons and two protons.

Detailed explanation-5: -NAD+ and FAD are oxidizing agents-that is, electron acceptors.