Question

In a TCA cycle, how many NADH₂ and FADH₂ are produced, respectively?

• A. 3 NADH₂, 1 FADH₂
• B. 2 NADH₂, 1 FADH₂
• C. 4 NADH₂, 1 FADH₂
• D. 4 NADH₂, 2 FADH₂

Answer 1

Answer: (A)

The tricarboxylic acid (TCA) cycle, also known as the Kreb's or citric acid cycle, is the main source of energy for cells and an important part of aerobic respiration. The cycle harnesses the available chemical energy of acetyl coenzyme A (acetyl CoA) into the reducing power of NADH₂ and FADH₂. Each molecule of acetyl CoA produces 3 NADH₂ and 1 FADH₂.