This is the site of protein synthesis in a neuron.

Options

A. Mitochondria
B. Nucleus
C. Nissl body
D. Dendrite

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks for the specific site of protein synthesis in a neuron. It provides four options: mitochondria, nucleus, nissl body, and dendrite.

2. **Identifying the Options:**
- **Mitochondria:** Primarily involved in energy production (ATP synthesis) and not directly in protein synthesis.
- **Nucleus:** Contains genetic material and is involved in the transcription of RNA, but it is not the site of protein synthesis itself.
- **Nissl Body:** Composed of rough endoplasmic reticulum (RER) and free ribosomes, which are directly involved in protein synthesis.
- **Dendrite:** Part of the neuron that receives signals, but not primarily involved in protein synthesis.

3. **Analyzing the Nissl Body:**
The Nissl body, also known as Nissl substance, is a large granular structure found in neurons. It contains rough endoplasmic reticulum and free ribosomes, which are essential for synthesizing proteins.

4. **Conclusion:**
Since the Nissl body contains the necessary components (RER and ribosomes) for protein synthesis, it is the correct answer.

5. **Final Answer:**
The site of protein synthesis in a neuron is the **Nissl body**.

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