In alcoholic fermentation, pyruvate is converted to ...

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In alcoholic fermentation, pyruvate is converted to ...

Alcoholic fermentation shows how cells regenerate NAD+ when oxygen is limited, allowing glycolysis to keep producing ATP. Pyruvate is first decarboxylated to acetaldehyde, releasing CO2. Then acetaldehyde is reduced to ethanol by alcohol dehydrogenase, using electrons from NADH and regenerating NAD+. This refreshed NAD+ lets glycolysis continue. The other paths don’t fit this process: converting pyruvate to oxaloacetate is an anaplerotic/gluconeogenic step, not part of fermentation; sending pyruvate into the citric acid cycle requires acetyl-CoA and aerobic conditions; producing lactate is the pathway of lactic acid fermentation, not alcoholic fermentation.

Alcoholic fermentation shows how cells regenerate NAD+ when oxygen is limited, allowing glycolysis to keep producing ATP. Pyruvate is first decarboxylated to acetaldehyde, releasing CO2. Then acetaldehyde is reduced to ethanol by alcohol dehydrogenase, using electrons from NADH and regenerating NAD+. This refreshed NAD+ lets glycolysis continue. The other paths don’t fit this process: converting pyruvate to oxaloacetate is an anaplerotic/gluconeogenic step, not part of fermentation; sending pyruvate into the citric acid cycle requires acetyl-CoA and aerobic conditions; producing lactate is the pathway of lactic acid fermentation, not alcoholic fermentation.

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