After donating electrons to the chain, NADH and FADH2 are converted to

After donating electrons to the chain, NADH and FADH2 are converted to

• A. They become ATP
• B. They become NADP+
• C. They are oxidized to NAD+ and FAD
• D. They are degraded

Answer: (C)

In cellular respiration, NADH and FADH2 act as electron carriers that deliver electrons to the mitochondrial electron transport chain. When they donate those electrons, they are oxidized back to their oxidized forms: NAD+ and FAD. This regeneration is essential so that glycolysis and the citric acid cycle can continue feeding more reduced equivalents into the chain. They aren’t turned into ATP themselves at this step, they aren’t converted to NADP+, and they aren’t degraded. The energy from their electrons drives proton pumping and ATP synthesis, while the carriers are recycled back to NAD+ and FAD.

In cellular respiration, NADH and FADH2 act as electron carriers that deliver electrons to the mitochondrial electron transport chain. When they donate those electrons, they are oxidized back to their oxidized forms: NAD+ and FAD. This regeneration is essential so that glycolysis and the citric acid cycle can continue feeding more reduced equivalents into the chain. They aren’t turned into ATP themselves at this step, they aren’t converted to NADP+, and they aren’t degraded. The energy from their electrons drives proton pumping and ATP synthesis, while the carriers are recycled back to NAD+ and FAD.