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 bound by a double membrane. Therefore, they do not count as a single membrane-bound organelle.

2. **Lysosome**: Lysosomes are bound by a single membrane. They contain hydrolytic enzymes for digestion. This counts as one single membrane-bound organelle.

3. **Peroxisome**: Peroxisomes are also bound by a single membrane. They contain enzymes that oxidize fatty acids and amino acids. This counts as another single membrane-bound organelle.

4. **Golgi Body**: The Golgi body (or Golgi apparatus) is made up of a series of flattened membrane-bound sacs and is bound by a single membrane. This counts as another single membrane-bound organelle.

5. **Nucleus**: The nucleus is bound by a double membrane (nuclear envelope). Therefore, it does not count as a single membrane-bound organelle.

6. **Nucleolus**: The nucleolus is not a membrane-bound organelle; it is a structure within the nucleus. Therefore, it does not count.

7. **Endoplasmic Reticulum (ER)**: The endoplasmic reticulum is also a membrane-bound organelle, but it is bound by a single membrane. This counts as another single membrane-bound organelle.

8. **Spherosome**: Spherosomes (or glyoxysomes) are bound by a single membrane. This counts as another single membrane-bound organelle.

9. **Ribosomes**: Ribosomes are not membrane-bound organelles; they are made up of RNA and proteins. Therefore, they do not count.

Now, let's summarize the organelles that are bound by a single membrane:

- Lysosome: 1
- Peroxisome: 2
- Golgi Body: 3
- Endoplasmic Reticulum (ER): 4
- Spherosome: 5

In total, there are **5 organelles** that are bound by a single membrane.

**Final Answer**: 5

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