Cell oganelle which is not bounded by any membrane

Options

A. Centriole
B. Spherosome
C. Vacuole
D. Ribosome

Answer

To identify the cell organelle that is not bounded by any membrane, we will analyze the given options step by step.

### Step-by-Step Solution:

1. **Understanding the Question**:
- We need to find a cell organelle that is not surrounded by a membrane. This means we are looking for non-membranous organelles.

2. **Analyzing Option 1: Centriole**:
- Centrioles are cylindrical structures made up of microtubules.
- They are located in the cytoplasm near the nucleus and are part of the centrosome.
- Centrioles are not surrounded by any membrane.
- **Conclusion**: Centrioles are non-membranous.

3. **Analyzing Option 2: Spherosome**:
- Spherosomes are organelles that are involved in lipid storage.
- They are surrounded by a single membrane.
- **Conclusion**: Spherosomes are membranous.

4. **Analyzing Option 3: Vacuole**:
- Vacuoles are storage organelles found in cells.
- They are also surrounded by a single membrane.
- **Conclusion**: Vacuoles are membranous.

5. **Analyzing Option 4: Ribosome**:
- Ribosomes are small, spherical structures that are the sites of protein synthesis.
- They do not have any surrounding membrane.
- **Conclusion**: Ribosomes are non-membranous.

6. **Final Conclusion**:
- From the analysis, we find that both centrioles and ribosomes are not bounded by any membrane.
- Therefore, the correct answer includes both **Centriole** and **Ribosome**.

### Final Answer:
The cell organelles which are not bounded by any membrane are **Centriole** and **Ribosome**.

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