Power of regeneration is poor in

Options

A. Brain cell
B. Bone cell
C. Chondroblasts
D. Striated muscles.

Answer

### Step-by-Step Solution:

1. **Understanding Regeneration**: Regeneration refers to the process by which organisms replace or restore lost or damaged tissues. Different cell types have varying abilities to regenerate.

2. **Analyzing the Options**: The options given are:
- Brain cell
- Bone cell
- Chondroblast
- Striated muscle

3. **Evaluating Each Option**:
- **Brain Cell**: Brain cells, or neurons, primarily exist in the G0 phase of the cell cycle, which is a resting state. They do not divide and have a very limited capacity for regeneration. Instead, they can form new connections (synapses) with other neurons but do not replace themselves.
- **Bone Cell**: Bone cells, specifically osteocytes, are involved in the maintenance and formation of bone tissue. They have a good capacity for regeneration.
- **Chondroblast**: Chondroblasts are responsible for the formation of cartilage. They also have the ability to regenerate.
- **Striated Muscle**: Striated muscle cells (skeletal muscle) can regenerate to some extent, especially through satellite cells that can differentiate and repair muscle tissue.

4. **Conclusion**: Among the options, brain cells have the poorest power of regeneration due to their permanent state in the G0 phase and lack of cellular machinery for division. Therefore, the correct answer is **brain cell**.

### Final Answer:
The power of regeneration is poor in **brain cells**.

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