Which part of neuron is covered by fatty sheath ?

Options

A. Axon
B. Cyton
C. Dendrite
D. Node of Ranvier.

Answer

**Step-by-Step Solution:**

1. **Identify the Parts of a Neuron**: A neuron consists of three main parts: the cell body (cytone), dendrites, and axon.

2. **Understand the Function of Each Part**:
- **Cytone**: The cell body, responsible for metabolic activities.
- **Dendrites**: Extensions that receive signals from other neurons.
- **Axon**: The part that transmits signals away from the cell body.

3. **Focus on the Question**: The question asks which part of the neuron is covered by a fatty sheath.

4. **Identify the Fatty Sheath**: The fatty sheath referred to in the question is known as the **myelin sheath**.

5. **Determine Where the Myelin Sheath is Located**: The myelin sheath surrounds the axon of the neuron. It provides insulation and increases the speed of nerve signal transmission.

6. **Evaluate the Options**:
- **Cytone**: No myelin sheath present.
- **Dendrite**: No myelin sheath present.
- **Axon**: Yes, the myelin sheath is present.
- **Node of Ranvier**: These are gaps between myelin sheaths and do not have myelin covering.
- **Friend wire**: Not a recognized part of a neuron.

7. **Conclusion**: The correct answer is **axon**, as it is the part of the neuron that is covered by the myelin sheath.

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