Fermentation

Introduction

• Fermentation is an anaerobic metabolic pathway that occurs when oxygen is not available.
• It involves the conversion of pyruvate molecules into other substances in the cytoplasm of the cell.

Types of Fermentation

1. Alcoholic Fermentation

• Occurs in plant cells and fungi, such as yeast cells.
• Pyruvate is converted into ethanol (alcohol) and carbon dioxide (CO2).
• This is an irreversible reaction.

2. Lactate Fermentation

• Occurs in animal cells.
• Pyruvate is converted into lactate (lactic acid).
• This is a reversible reaction.

Anaerobic vs. Aerobic Conditions

• In the presence of oxygen (aerobic conditions), pyruvate molecules enter the citric acid cycle, leading to efficient ATP production.
• In the absence of oxygen (anaerobic conditions), pyruvate undergoes fermentation as an alternative metabolic pathway.

ATP Production

• Fermentation results in much less ATP production compared to aerobic respiration.
• This is because the complete oxidation of glucose does not occur during fermentation.

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Fermentation

Summary

• Fermentation is an anaerobic metabolic pathway used when oxygen is unavailable.
• Two types of fermentation include alcoholic fermentation (in plant and fungal cells) and lactate fermentation (in animal cells).
• Fermentation results in the conversion of pyruvate into different substances, with significantly less ATP production compared to aerobic respiration.