How much amount of energy is released in lactic acid and alcoholic fermentation?

Answer

### Step-by-Step Solution:

1. **Understanding Anaerobic Respiration**:
- Anaerobic respiration occurs in the absence of oxygen and includes processes such as lactic acid fermentation and alcoholic fermentation.

2. **Glycolysis**:
- Both types of fermentation start with glycolysis, where one molecule of glucose is converted into two molecules of pyruvate. This process yields a net gain of 2 ATP molecules.

3. **Lactic Acid Fermentation**:
- In lactic acid fermentation, which occurs in human muscles, the pyruvate is directly converted into lactic acid. The energy yield from this process is minimal.

4. **Alcoholic Fermentation**:
- In alcoholic fermentation, which occurs in yeast and some fungi, pyruvate is first converted into acetaldehyde and then into ethyl alcohol.

5. **Energy Yield Comparison**:
- In aerobic respiration, a total of 38 ATP molecules can be produced from one molecule of glucose.
- In contrast, both lactic acid and alcoholic fermentation yield significantly less energy. Specifically, the energy released during fermentation is less than 7% of that produced in aerobic respiration, which is approximately 5% of the energy.

6. **Conclusion**:
- Therefore, the amount of energy released in lactic acid fermentation is about 2 ATP (from glycolysis), and in alcoholic fermentation, it is also around 2 ATP, with both processes being much less efficient than aerobic respiration.