Q. Oxidative phosphorylation is :
(a) Addition of phosphate group in ATP
(b) Formation of ATP by energy released from electrons removed during substrate oxidation
(c) Formation of ATP by transfer of phosphate group from a substrate to ADP
(d) Oxidation of phosphate group in ATP
Solution :
Correct option : B Oxidative phosphorylation, refers to the synthesis of ATP by ADP and Pi driven by energy released from the oxidation of reducing powers NADH and FADH by transfer of their electrons through electron transport chain to oxygen. Electron transport chain is present in inner mitochondrial membrane and passes the electrons down a series of carriers and pump protons into the intermembrane space. Oxygen serves as final electron acceptor and the resulting proton gradient serves as energy source for the enzyme ATP synthase to synthesize ATP. Therefore, the correct answer is option B.