Saltatory conduction of impulse occurs in

Options

A. Myelinated nerve fibres
B. Nonmyelinated fibres
C. Both of these
D. None of these

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks where saltatory conduction of nerve impulses occurs. We need to identify the type of nerve fibers involved in this process.

2. **Identifying Neuron Structure**: Neurons, the functional units of the nervous system, consist of a cell body, dendrites, and an axon. The axon is the long part that conducts impulses away from the cell body.

3. **Role of Myelin Sheath**: The axon is often surrounded by a myelin sheath, which is formed by Schwann cells. This sheath acts as an insulator and prevents the flow of ions across the axonal membrane, except at specific points.

4. **Nodes of Ranvier**: The myelin sheath is absent at intervals along the axon, known as the Nodes of Ranvier. These nodes are crucial for the conduction of nerve impulses.

5. **Mechanism of Saltatory Conduction**: In myelinated fibers, the action potential (nerve impulse) jumps from one Node of Ranvier to the next, rather than traveling continuously along the axon. This jumping mechanism is called saltatory conduction.

6. **Speed of Conduction**: Saltatory conduction is much faster than conduction in non-myelinated fibers, with speeds reaching up to 200 meters per second.

7. **Conclusion**: Therefore, saltatory conduction of nerve impulses occurs specifically in myelinated nerve fibers.

### Final Answer:
Saltatory conduction of impulse occurs in **myelinated nerve fibers**.

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