Why does the Krebs cycle stop when oxygen is not available?

Answer and explanation

Correct answer: C. Reduced NAD and FAD cannot be reoxidised by the electron transport chain

  1. Step 1: The chain needs oxygen to accept electrons. Step 2. Without it NAD and FAD are not regenerated, so the cycle stops. Answer: the coenzymes are not reoxidised. Why not the others: these are not the mechanism.

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