Myelin sheath of nerve fibres is produced by

Options

A. Nissl's granules
B. Schwann cells
C. Nodes of Ranvier
D. Neurotransmitters

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks about the origin of the myelin sheath in nerve fibers. Myelin sheath is an important structure in neurons that plays a crucial role in the conduction of nerve impulses.

2. **Identifying the Options**: The options given are:
- Nasal granules
- Schwann cells
- Node of Ranvier
- Neurotransmitters

3. **Analyzing Each Option**:
- **Nasal Granules**: These are small granules found in the cell body of neurons and are not involved in the formation of the myelin sheath.
- **Schwann Cells**: These are specialized glial cells in the peripheral nervous system responsible for the formation of the myelin sheath around nerve fibers.
- **Node of Ranvier**: These are gaps in the myelin sheath and do not produce the myelin itself.
- **Neurotransmitters**: These are chemicals that transmit signals across a synapse between neurons and are not involved in the formation of the myelin sheath.

4. **Conclusion**: Based on the analysis, the correct answer is **Schwann cells**, as they are responsible for producing the myelin sheath around the nerve fibers.

5. **Final Answer**: The myelin sheath of nerve fibers is produced by **Schwann cells**.

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