Question

In comparing oxidative and substrate-level phosphorylation, which of the following is unique to oxidative phosphorylation?

	A.	ATP synthesis fueled by a proton motive force generated as a result of the movement of electrons down an electron transport chain.
	B.	ATP synthesis that occurs as a result of coupling the exergonic breakdown of a high-energy organic molecule to phosphorylation
	C.	glucose oxidation
	D.	NADH production

Answer 1

Option a is correct.

In oxidative phosphorylation ATP formation inside the mitochondria requires

a) proton concentration gradient across the inner mitochondrial membrane

B)the proton pump

C)proton motive force

D) the electron transport chain

E)the enzyme ATPase

But in substrate level phosphorylation ATP is synthesized by conversion of higher energy substrate to lower energy product and used some of the released energy to transfer a phosphoryl group to ADP or GDP from other phosphorylated compound. Substrate level phosphorylation is not associated with ETC.

Option b refers to substrate level phosphorylation so it's not correct.

Option c is also incorrect because during glucose breakdown both oxidative and substrate level phosphorylation takes place.

Option D is also incorrect as oxidative phosphorylation is not associated with NADH production.