Question

Explain please!

1) How many molecules of carbon dioxide are produced per glucose during the citric acid cycle?

2) How many molecules of FADH2 are produced per acetyl CoA during the citric acid cycle?

3) How many molecules of ATP (net) are produced via substrate-level phosphorylation per glucose during glycolysis?

Answer 1

1. 4 molecules of CO2 are produced per glucose during the citric acid cycle. 1 molecule of acetyl CoA is used per citric acid cycle. 2 molecules of CO2 releases per citric acid cycle. Glucose molecule produces 2 pyruvate molecules which converted into 2 acetyl CoA. Thus, for consumption 2 acetyl CoA, 2 citric acid cycle will be require and thus 4 molecules of CO2 will be produced per glucose molecule during citric acid cycle.

2. One molecule of FADH2 are produced per acetyl CoA during the citric acid cycle. 1 molecule of acetyl CoA is used per citric acid cycle which produces one molecule of FADH2, and 3 molecules of NADH.

3. 2 molecules of ATP are produced via substrate-level phosphorylation per glucose during glycolysis. Actually four molecules of ATP are produced during glycolysis via substrate level phosphorylation but the first step of glycolysis consumes 2 molecules of ATP and thus net ATP gain is 2.