Why does FADH₂ contribute fewer ATP per molecule (<del>1.5) than NADH (</del>2.5)?
- Acheck_circle
FADH₂ delivers electrons further along the ETC, bypassing one proton-pumping complex
- B
FADH₂ is regenerated more slowly, limiting how often it can deliver its electrons
- C
FADH₂ produces protons in the matrix instead of pumping them into the intermembrane space
- D
FADH₂ donates electrons to NAD⁺ first, losing some energy to redox conversion
Explanation
NADH enters at Complex I, FADH₂ at Complex II — fewer protons are pumped per FADH₂, yielding less ATP.