MDCAT Biology MCQ #452

When electrons from NADH and FADH2 are passed through the ETC, they yield different amounts of ATP. Why does NADH yield more?

MDCAT Biology MCQ #452

  1. Question 1

    Q1. When electrons from NADH and FADH2 are passed through the ETC, they yield different amounts of ATP. Why does NADH yield more?

    • A) NADH produces 2 ATP while FADH2 produces 3 ATP
    • B) NADH produces 3 ATP while FADH2 produces 2 ATP
    • C) Both molecules yield exactly 4 ATP during chemiosmosis
    • D) NADH is oxidized at the end of the chain by oxygen

    Answer: NADH produces 3 ATP while FADH2 produces 2 ATP

    Explanation: NADH enters at Complex I and yields 3 ATP, while FADH2 enters at Complex II and yields only 2 ATP.