Myelinated and unmyelinated nerve fibres are found in PNS respectively are

Answer

### Step-by-Step Solution:

1. **Understanding Nerve Fibers**: The peripheral nervous system (PNS) contains two types of nerve fibers: myelinated and unmyelinated. It is essential to know the characteristics of each type.

2. **Myelinated Nerve Fibers**: Myelinated nerve fibers are those that are covered with a myelin sheath. This sheath is formed by Schwann cells, which wrap around the axon of the nerve fiber. The presence of myelin increases the speed of nerve impulse conduction.

3. **Location of Myelinated Nerve Fibers**: In the PNS, myelinated nerve fibers are primarily found in the spinal nerves and cranial nerves. These fibers are crucial for rapid signal transmission.

4. **Unmyelinated Nerve Fibers**: Unmyelinated nerve fibers, on the other hand, do not have a myelin sheath. This absence of myelin results in slower conduction of nerve impulses compared to myelinated fibers.

5. **Location of Unmyelinated Nerve Fibers**: Unmyelinated nerve fibers are commonly found in the somatic nerve fibers. These fibers are associated with the autonomic nervous system and are involved in various involuntary functions.

6. **Final Answer**: Therefore, the myelinated nerve fibers in the PNS are found in the spinal and cranial nerves, while the unmyelinated nerve fibers are found in the somatic nerve fibers.

### Summary of the Answer:
- **Myelinated Nerve Fibers**: Found in spinal and cranial nerves.
- **Unmyelinated Nerve Fibers**: Found in somatic nerve fibers.

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