Introduction:
- Anaerobic respiration is a process by which cells produce energy without the use of oxygen.
- It is a less efficient way of generating energy compared to aerobic respiration.
Occurrence:
- Anaerobic respiration occurs when there is a shortage of oxygen, such as during intense physical activity or in environments with low oxygen levels.
Types of Anaerobic Respiration:
Lactic Acid Fermentation:
- Occurs in muscle cells when oxygen is scarce, like during vigorous exercise.
- Pyruvate (from glycolysis) is converted into lactic acid.
- Lactic acid can build up, causing muscle fatigue and soreness.
Chemical Reaction:
Pyruvate (from glycolysis) + NADH → Lactic Acid + NAD+
C3H4O3 (pyruvate) + NADH → C3H6O3 (lactic acid) + NAD+
Alcoholic Fermentation:
- Happens in some microorganisms like yeast.
- Pyruvate is converted into ethanol (alcohol) and carbon dioxide.
- Used in the production of bread, beer, and wine.
Chemical Reaction:
Pyruvate (from glycolysis) → Ethanol + Carbon Dioxide
C3H4O3 (pyruvate) → C2H5OH (ethanol) + CO2 (carbon dioxide)
Energy Production:
- Anaerobic respiration produces much less energy (ATP) compared to aerobic respiration.
- This is because the complete breakdown of glucose doesn’t occur in the absence of oxygen.
Importance:
- Anaerobic respiration is a temporary solution when the oxygen supply is insufficient.
- It helps to provide some energy to cells when needed.
Waste Products:
- Lactic acid or ethanol and carbon dioxide are the waste products of anaerobic respiration.
Duration:
- Anaerobic respiration is usually a short-term solution, and cells switch back to aerobic respiration once oxygen becomes available.
Contrast with Aerobic Respiration:
- In contrast to aerobic respiration, which is more efficient and produces a lot of ATP, anaerobic respiration is less efficient and produces much less ATP.