When Paramoecium was subjected to X-ray its macronucleus degenerate and one of the following stopped

Options

A. Locomotion, digestion , osmoregulation
B. Reproduction, digestion, locomotion
C. Reproduction, Locomotion, osmoregulation
D. Reproduction, osmoregulation

Answer

To solve the question regarding the effects of X-ray exposure on Paramecium, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Macronucleus**:
- The macronucleus in Paramecium is responsible for regulating various metabolic activities, including digestion and osmoregulation. It plays a crucial role in the overall functioning of the cell.

2. **Identify the Effects of X-ray Exposure**:
- When Paramecium is subjected to X-ray radiation, it leads to the degeneration of the macronucleus. This degeneration disrupts the normal metabolic processes that the macronucleus controls.

3. **Analyze the Options Given**:
- The question provides several options regarding which function stops when the macronucleus degenerates:
- **Locomotion**
- **Digestion**
- **Osmoregulation**
- **Reproduction**

4. **Determine the Correct Function that Stops**:
- Since the macronucleus is involved in digestion and osmoregulation, its degeneration would most likely lead to a failure in these processes.
- Among the options, osmoregulation is particularly critical because it involves maintaining the balance of water and salts within the cell, which is essential for cell survival.

5. **Conclusion**:
- Therefore, when the macronucleus degenerates due to X-ray exposure, the function that stops is **osmoregulation**.

### Final Answer:
The correct answer is **Osmoregulation**.

---