Question

One function of both alcohol fermentation and lactic acid fermentation is to

	A.	reduce FAD+ to FADH2.
	B.	oxidize NADH to NAD+.
	C.	reduce NAD+ to NADH.
	D.	reduce FADH2 to FAD+.
	E.	None of these answers are correct

Answer 1

Answer. B) oxidize NADH to NAD⁺

Solution: Lactic acid fermentation, alcoholic fermentation, which is also referred to as ethanol fermentation. When oxygen is low, as in muscle during vigorous contraction, the oxidation of NADH to NAD⁺ by the electron transport chain becomes insufficient to maintain glycolysis. Under these conditions, NAD⁺ is regenerated by reduction of pyruvate to lactate by lactate dehydrogenase.

Pyruvate + NADH + H⁺ = lactate + NAD⁺