Question

Which steps of the citric acid cycle generate reduced coenzymes necessary in the production of ATP?

Question 18 options:

	A) Steps 2, 3, 4, and 7
	B) Steps 3, 4, 5, and 7
	C) Steps 3, 4, 6, and 8
	D) Steps 1, 4, 7, and 8

Answer 1

Answer is Steps, 3, 4, 6 and 8.

The reduces coenzymes necessary in production of ATP formed during Citric acid cycle are NADH and FADH2.

In step 3, isocitrate (6-C) is oxidized and a molecule of carbon dioxide is removed forming the molecule alpha-ketoglutarate (5-C). During this oxidation, NAD+ is reduced to NADH and H+. In step 4, alpha-ketoglutarate (5-C) oxidizes evolving carbon dioxide and coenzyme A is added to form succinyl-CoA (4-C). During this NAD+ is reduced to NADH and H+. In step 6, succinate is oxidized to fumarate wherein FAD is reduced to FADH2. In step 8, malate is oxidized to produce oxaloacetate wherein NAD+ is reduced to NADH and H+.