One NADH is oxidised by the electron transport system with subsequent. production of

Correct option is C

Correct Answer: C. Three ATP

• NADH (Nicotinamide Adenine Dinucleotide) is a high-energy electron carrier produced in processes like glycolysis and the Krebs cycle.

• During oxidative phosphorylation in the electron transport system (ETS), one NADH donates electrons, which flow through complexes I–IV in the mitochondrial inner membrane.

• This electron flow powers proton pumping, creating a proton gradient used by ATP synthase to generate ATP.

• Each NADH typically results in the production of 3 ATP molecules (although some texts now estimate ~2.5 ATP due to revised P/O ratios based on newer biochemistry findings).

• FADH₂, another electron carrier, yields 2 ATP (or approximately 1.5 ATP in modern estimates).

• This ATP production occurs during aerobic respiration, specifically in the inner mitochondrial membrane.

• The total ATP yield from 1 glucose molecule is about 36–38 ATP in traditional texts, including ATP from glycolysis, Krebs cycle, and ETS.

• Revised ATP yield (based on updated biochemistry):

  • 1 NADH ≈ 2.5 ATP

  • 1 FADH₂ ≈ 1.5 ATP