Saltatory conduction occurs in :

Options

A. Non-myelinaied fibers
B. Myelinated fibers
C. Both of them
D. None of them

Answer

**Step-by-Step Solution:**

1. **Understanding Saltatory Conduction**: Saltatory conduction refers to the process by which nerve impulses jump from one node of Ranvier to another along a myelinated axon. This method of conduction is faster than continuous conduction that occurs in non-myelinated fibers.

2. **Identifying the Structure**: Myelinated fibers are characterized by the presence of myelin sheaths, which are insulating layers that cover the axon. These sheaths are interrupted at intervals by nodes of Ranvier.

3. **Mechanism of Saltatory Conduction**: In myelinated fibers, the action potential is generated only at the nodes of Ranvier. The myelin sheath prevents ion flow across the membrane in the regions covered by myelin, thus allowing the action potential to "jump" from node to node. This jumping significantly increases the speed of nerve impulse transmission.

4. **Conclusion**: Based on the definition and mechanism of saltatory conduction, it is clear that this phenomenon occurs specifically in myelinated fibers, not in non-myelinated fibers.

5. **Final Answer**: Saltatory conduction occurs in myelinated fibers.

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