Nodes of Ranvier occur in

Options

A. Cell body
B. Right atrium
C. Right ventricle
D. Medullated nerve fibres.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks where the "nodes of Ranvier" occur. This requires knowledge of the structure of nerve fibers.

2. **Identifying the Options**: The options provided are:
- Option 1: Cell body
- Option 2: Right atrium
- Option 3: Right ventricle
- Option 4: Medulated nerve fiber

3. **Analyzing Each Option**:
- **Option 1 (Cell body)**: The cell body is part of a neuron but does not contain nodes of Ranvier. Therefore, this option is incorrect.
- **Option 2 (Right atrium)**: The right atrium is a chamber of the heart and does not relate to nerve fibers. Thus, this option is incorrect.
- **Option 3 (Right ventricle)**: Similar to the right atrium, the right ventricle is also a chamber of the heart and is not related to nodes of Ranvier. This option is incorrect.
- **Option 4 (Medulated nerve fiber)**: This option refers to myelinated nerve fibers, which are characterized by the presence of nodes of Ranvier. Therefore, this option is correct.

4. **Conclusion**: Based on the analysis, the correct answer is that nodes of Ranvier occur in **medulated nerve fibers**.

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