Question

The conversion of 1 mol of pyruvate to 3 mol of CO₂ via pyruvate dehydrogenase and the citric acid cycle also yields _____ mol of NADH, _____ mol of FADH₂, and _____ mol of ATP (or GTP).

Answer 1

The conversion of 1 mol of pyruvate to 3 mol of CO₂ entails the production of 4 mol of NADH, 1 mol of FADH₂, and 1 mol of ATP (or GTP) through pyruvate dehydrogenation and the citric acid cycle.

Step-by-step explanation:

The conversion of 1 mol of pyruvate to 3 mol of CO₂ via pyruvate dehydrogenase and the citric acid cycle also yields 4 mol of NADH, 1 mol of FADH₂, and 1 mol of ATP (or GTP). This is because during the oxidation of pyruvate to acetyl-CoA by pyruvate dehydrogenase, 1 mol of NADH is produced.

Then each acetyl-CoA molecule enters the citric acid cycle, which completes one turn to give off 2 mol of CO₂ and in the process, produces 3 mol of NADH, 1 mol of FADH₂, and 1 mol of GTP (which can be converted to ATP), per turn of the cycle. As 1 mol of acetyl-CoA is derived from 1 mol of pyruvate, the total yield from the conversion of 1 mol of pyruvate through one full citric acid cycle turn is:

• 4 mol of NADH (1 from pyruvate dehydrogenase + 3 from citric acid cycle)
• 1 mol of FADH₂
• 1 mol of ATP or GTP