1. By glycolysis, glucose is converted into pyruvate.
1. By fermentation, pyruvate is converted into alcohol or lactic acid.
2. It takes place with or without the presence of oxygen.
2. It takes place in presence of oxygen.
3. Net gain of ATP molecule.
3. No net gain of ATP molecule.
4. The pyruvate enters the citric acid cycle.
4. The pyruvate will be converted either to ethanol or lactic acid and NAD+ regenerated.