Oxidative phosphorylation is an energetic process in cells and generates energy in the form of ATP (adenosine triphosphate) molecules. This process is a result of coupling of two different reactions. The first reaction is the transfer of electrons from NADH molecules (formed during glycolysis process), which is an electron donor, to oxygen (which is an electron acceptor). This is an energetic reactions and releases energy, which is used to transport protons across the membrane, thus generating a proton gradient across the membrane (known as proton motive force), ATP generation takes places when these protons return back to the cell. These two processes are coupled to each other and in total, 26 ATP molecules are produced for every mole of glucose completely oxidized. In total, 10 NADH molecules are generated for each molecule of glucose and oxidative posphorylation releases 26 molecules of ATP.
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