Which cells of PNS secrete myelin sheath around the nerves?

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks which cells in the Peripheral Nervous System (PNS) are responsible for secreting the myelin sheath around nerves.

2. **Identifying the PNS**: The Peripheral Nervous System (PNS) is one of the two main divisions of the nervous system, the other being the Central Nervous System (CNS). The PNS consists of all the nerves that branch out from the brain and spinal cord.

3. **Understanding Neurons**: Neurons are the fundamental units of the nervous system. They consist of three main parts: the cell body, dendrites (which receive signals), and the axon (which transmits signals).

4. **Role of Myelin Sheath**: The myelin sheath is a protective covering that surrounds the axon of some neurons. It is essential for the proper functioning of the nervous system as it helps in the rapid transmission of electrical signals along the axon.

5. **Identifying the Cells that Form Myelin Sheath**: In the PNS, the cells responsible for forming the myelin sheath are called Schwann cells. These cells wrap around the axon and secrete the myelin sheath.

6. **Conclusion**: Therefore, the cells of the PNS that secrete the myelin sheath around the nerves are Schwann cells.

### Final Answer:
**Schwann cells** are the cells of the Peripheral Nervous System (PNS) that secrete the myelin sheath around the nerves.

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