MUSCLE PHYSIOLOGY

Detailed explanation-1: -In this shuttle, NADH is oxidized to NAD+ in the cytosol and NAD+ is reduced to NADH in mitochondria. NAD+ is used as an electron acceptor during glycolysis, whereas NADH is used by mitochondrial complex I to drive the mitochondrial electron transport chain (ETC).

Detailed explanation-2: -NAD exists in two forms: an oxidized and reduced form, abbreviated as NAD+ and NADH (H for hydrogen), respectively.

Detailed explanation-3: -NAD+ is the oxidized form of the molecule; NADH is the reduced form of the molecule after it has accepted two electrons and a proton (which together are the equivalent of a hydrogen atom with an extra electron). When electrons are added to a compound, they are reduced.

Detailed explanation-4: -NADPH is the reduced form of NADP+. NADP+ differs from NAD+ by the presence of an additional phosphate group on the 2’ position of the ribose ring that carries the adenine moiety. This extra phosphate is added by NAD+ kinase and removed by NADP+ phosphatase.

Detailed explanation-5: -In the process of glycolysis, NAD+ is reduced to form NADH + H+. If NAD+ is not present, glycolysis will not be able to continue. During aerobic respiration, the NADH formed in glycolysis will be oxidized to reform NAD+ for use in glycolysis again.