Which step of aerobic respiration produces the most ATP?

• A. Citric Acid Cycle
• B. Pyruvate Oxidation
• C. Glycolysis
• D. Electron Transport Chain

Answer: (D)

Verified step by step guidance

1. Understand that aerobic respiration is a process that cells use to convert biochemical energy from nutrients into ATP, and it involves several stages: Glycolysis, Pyruvate Oxidation, Citric Acid Cycle, and Electron Transport Chain.
2. Recall that Glycolysis occurs in the cytoplasm and breaks down glucose into pyruvate, producing a small amount of ATP and NADH.
3. Recognize that Pyruvate Oxidation occurs in the mitochondria, where pyruvate is converted into acetyl-CoA, producing NADH and releasing carbon dioxide, but not directly producing ATP.
4. Identify that the Citric Acid Cycle (also known as the Krebs Cycle) takes place in the mitochondrial matrix, generating ATP, NADH, and FADH2 by oxidizing acetyl-CoA.
5. Understand that the Electron Transport Chain, located in the inner mitochondrial membrane, uses electrons from NADH and FADH2 to create a proton gradient that drives ATP synthesis through oxidative phosphorylation, producing the most ATP in aerobic respiration.