Overall is the citric acid cycle an endergonic or paregoric

Overall, is the citric acid cycle an endergonic or paregoric pathway? What is the net energy yield (ATP, FADH_2, and NADH) for one pyruvate completing the cycle? How many CO_2 are formed from one pyruvate? Compare the number of carbon atoms in the pyruvate and CO_2 s.

Solution

1. Citric acid cycle is exergonic producing 2 ATP (GTP) on overall cycle. Three molecules of NADH and one molecule of FADH₂ are produced during citric acid cycle.

2. A pyruvate molecule produces 1 NADH by oxidation. One NADH molecule is accounted for 2.5 moles of ATP.

3. One pyruvate molecule forms one CO₂ molecule. Pyruvate molecule contains 3 carbons.