Below are given a few cell organelles :
(a) Nucleus
(b) Lysosomes
(c) Peroxisomes
(d) ER
(e) Mitochondria
(f) Centrioles
(g) Plastids
Select the correct choice of organelles not bounded by two lipoprotein membranes.

Options

A. b, c, d, f
B. a, e, f
C. d, a , e , g
D. b, c, f

Answer

To solve the question of identifying the cell organelles that are not bounded by two lipoprotein membranes, we will analyze each organelle listed:

1. **Nucleus**:
- The nucleus is surrounded by a double membrane known as the nuclear envelope. Therefore, it is a double membrane-bound organelle.
- **Conclusion**: Not included.

2. **Lysosomes**:
- Lysosomes are bounded by a single membrane. They contain digestive enzymes that break down waste materials and cellular debris.
- **Conclusion**: Included.

3. **Peroxisomes**:
- Peroxisomes are also bounded by a single membrane. They contain enzymes that oxidize fatty acids and amino acids.
- **Conclusion**: Included.

4. **Endoplasmic Reticulum (ER)**:
- The endoplasmic reticulum is a single membrane-bound organelle. It comes in two forms: rough ER and smooth ER, both of which are involved in protein and lipid synthesis.
- **Conclusion**: Included.

5. **Mitochondria**:
- Mitochondria are surrounded by two membranes: an outer membrane and an inner membrane. They are known as the powerhouse of the cell.
- **Conclusion**: Not included.

6. **Centrioles**:
- Centrioles are not membrane-bound organelles. They are cylindrical structures made of microtubules and play a role in cell division.
- **Conclusion**: Included.

7. **Plastids**:
- Plastids, such as chloroplasts, are also double membrane-bound organelles found in plant cells. They are involved in photosynthesis and storage.
- **Conclusion**: Not included.

Now, summarizing the organelles that are not bounded by two lipoprotein membranes:
- Lysosomes (single membrane)
- Peroxisomes (single membrane)
- Endoplasmic Reticulum (single membrane)
- Centrioles (no membrane)

Thus, the correct choice of organelles not bounded by two lipoprotein membranes is:
**B, C, D, F** (Lysosomes, Peroxisomes, Endoplasmic Reticulum, Centrioles).