In anaerobic respiration, pyruvic acid in muscles forms

Options

A. ATP
B. Lactic acid
C. Acetyl Co- A
D. NAD

Answer

### Step-by-Step Solution:

1. **Understanding Anaerobic Respiration**:
- Anaerobic respiration occurs in the absence of oxygen. It is a form of respiration where glucose is partially broken down to produce energy.

2. **Formation of Pyruvic Acid**:
- During glycolysis, glucose is broken down into pyruvic acid. This process occurs regardless of whether oxygen is present or not.

3. **Anaerobic Conditions in Muscles**:
- In muscle cells, when oxygen is scarce (like during intense exercise), pyruvic acid does not undergo aerobic respiration. Instead, it undergoes fermentation.

4. **Conversion of Pyruvic Acid**:
- Under anaerobic conditions in human muscles, pyruvic acid is converted into lactic acid. This process is known as lactic acid fermentation.

5. **Final Products**:
- The primary product of this anaerobic process in muscle cells is lactic acid, along with some water.

6. **Conclusion**:
- Therefore, in anaerobic respiration, pyruvic acid in muscles forms lactic acid.

### Answer:
In anaerobic respiration, pyruvic acid in muscles forms **lactic acid**.

---