If a living cell is placed anaerobic condition its

Options

A. mitochondria will multiply
B. mitochondria will disappear
C. ER will disappear
D. mitochondria and ribosomes multiply speedly

Answer

### Step-by-Step Solution:

1. **Understanding Anaerobic Conditions**:
- Anaerobic conditions refer to environments where oxygen is not available. In such conditions, cells rely on anaerobic respiration to generate energy.

2. **Role of Mitochondria**:
- Mitochondria are known as the powerhouses of the cell and are primarily involved in aerobic respiration, which requires oxygen. In anaerobic conditions, the need for mitochondria decreases since the cell does not perform aerobic respiration.

3. **Analyzing the Options**:
- **Option A: Mitochondria will multiply**: This is incorrect because anaerobic conditions do not promote the multiplication of mitochondria, which are essential for aerobic respiration.
- **Option B: Mitochondria will disappear**: This is a plausible option since anaerobic respiration does not require mitochondria, leading to their potential disappearance.
- **Option C: ER will disappear**: The endoplasmic reticulum (ER) is involved in protein synthesis and transport, and its function is not directly affected by the presence or absence of oxygen. Therefore, this option is incorrect.
- **Option D: Mitochondria and ribosomes multiply speedily**: This option is also incorrect as it suggests conditions favorable for aerobic respiration, which is not the case in anaerobic environments.

4. **Conclusion**:
- Based on the analysis of each option, the correct answer is that "mitochondria will disappear" when a living cell is placed under anaerobic conditions.

### Final Answer:
**The correct answer is: Mitochondria will disappear.**

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