Nissl granules occur in which part and what is their function?

Options

A. Neurons and help in nutrition & increase metabolic activity of neuron
B. Blood and help in nutrition and excretion
C. Sarcoplasm and help in contraction
D. Mucous cell and secrete mucous

Answer

**Step-by-Step Solution:**

1. **Identify the Location of Nissl Granules:**
- Nissl granules, also known as Nissl bodies or tigroid substance, are primarily found in neurons. They are large granular bodies that are characteristic of the cell bodies of neurons.

2. **Understand the Composition of Nissl Granules:**
- Nissl granules are composed of rough endoplasmic reticulum (RER) and free ribosomes. The rough endoplasmic reticulum is responsible for the synthesis of proteins, and the presence of ribosomes gives it a granular appearance.

3. **Determine the Function of Nissl Granules:**
- The main function of Nissl granules is to serve as the site for protein synthesis. This is crucial for the metabolic activities of neurons, as proteins are essential for various cellular functions, including the maintenance and repair of neuronal structures.

4. **Summarize the Findings:**
- Nissl granules are found in neurons and play a vital role in increasing the nutrition and metabolic activity of these cells through protein synthesis.

**Final Answer:**
Nissl granules occur in neurons, and their function is to serve as the site for protein synthesis, thereby increasing the nutrition and metabolic activity of neurons.

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