Myelin sheath is the covering of

Options

A. Muscle cell
B. Axon
C. Blood vessels
D. Osteocyte

Answer

**Step-by-Step Solution:**

1. **Understanding the Myelin Sheath**: The myelin sheath is a protective covering that surrounds certain types of nerve fibers, specifically the axons of neurons.

2. **Identifying the Function of the Myelin Sheath**: Its primary function is to insulate the axon, which helps in the rapid transmission of electrical impulses along the nerve cells.

3. **Analyzing the Options**: The question provides four options: muscle cell, axon, blood vessels, and osteocyte. We need to determine which of these is covered by the myelin sheath.

4. **Evaluating Each Option**:
- **Muscle Cell**: Muscle cells do not have a myelin sheath.
- **Axon**: Axons are indeed covered by the myelin sheath.
- **Blood Vessels**: Blood vessels do not have a myelin sheath.
- **Osteocyte**: Osteocytes are bone cells and do not have a myelin sheath.

5. **Conclusion**: Based on the evaluation, the correct answer is that the myelin sheath is the covering of the axon.

**Final Answer**: The myelin sheath is the covering of the axon.

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