How many of the following cell organelles are bound by a single membrane ? Mitochondria, Lysosome, peroxisome , Golgi body, Nucleus , Nucleolus, ER , Spherosome , Ribosomes

Options

A. 4
B. 5
C. 6
D. 7

Answer

To determine how many of the listed cell organelles are bound by a single membrane, we will analyze each organelle one by one:

1. **Mitochondria**:
- Mitochondria are double membrane-bound organelles. They have an outer membrane and an inner membrane.
- **Conclusion**: Not counted.

2. **Lysosome**:
- Lysosomes are membrane-bound organelles that contain hydrolytic enzymes for digestion. They are surrounded by a single membrane.
- **Conclusion**: Counted.

3. **Peroxisome**:
- Peroxisomes are also single membrane-bound organelles that contain enzymes for various metabolic reactions, including the breakdown of fatty acids and detoxification.
- **Conclusion**: Counted.

4. **Golgi Body**:
- The Golgi apparatus (or Golgi body) is made up of flattened membranous sacs and is surrounded by a single membrane.
- **Conclusion**: Counted.

5. **Nucleus**:
- The nucleus is a double membrane-bound organelle, consisting of an inner and outer nuclear membrane.
- **Conclusion**: Not counted.

6. **Nucleolus**:
- The nucleolus is a non-membrane-bound structure found within the nucleus. It is involved in ribosome production.
- **Conclusion**: Not counted.

7. **Endoplasmic Reticulum (ER)**:
- The endoplasmic reticulum is a network of membranes and is considered a single membrane-bound organelle.
- **Conclusion**: Counted.

8. **Spherosome**:
- Spherosomes (also known as oil bodies) are single membrane-bound organelles involved in lipid storage.
- **Conclusion**: Counted.

9. **Ribosomes**:
- Ribosomes are not membrane-bound organelles; they are made of RNA and proteins and are involved in protein synthesis.
- **Conclusion**: Not counted.

Now, let's summarize the organelles that are bound by a single membrane:
- Lysosome
- Peroxisome
- Golgi Body
- Endoplasmic Reticulum
- Spherosome

**Total Count**: 5 organelles are bound by a single membrane.

**Final Answer**: 5

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