Organelle covered by double membrane is

Options

A. Nucleus
B. Mitochondrion
C. Plastid
D. All the above

Answer

To answer the question regarding which organelle is covered by a double membrane, we can analyze each of the options provided:

### Step-by-Step Solution:

1. **Identify the Organelles**: The options given are:
- Option 1: Nucleus
- Option 2: Mitochondria
- Option 3: Plastid
- Option 4: All of the above

2. **Analyze the Nucleus**:
- The nucleus is a vital organelle found in eukaryotic cells.
- It contains the cell's genetic material (DNA) and is responsible for controlling cellular activities.
- The nucleus is surrounded by a double membrane known as the nuclear envelope.
- **Conclusion**: The nucleus is covered by a double membrane.

3. **Analyze the Mitochondria**:
- Mitochondria are known as the powerhouse of the cell because they produce energy through cellular respiration.
- They are also surrounded by a double membrane, consisting of an outer membrane and an inner membrane.
- **Conclusion**: Mitochondria are covered by a double membrane.

4. **Analyze the Plastid**:
- Plastids are primarily found in plant cells and some protists like euglenoids.
- They are involved in various functions such as photosynthesis (chloroplasts), storage (amyloplasts), and pigment synthesis (chromoplasts).
- Plastids are also enclosed by a double membrane.
- **Conclusion**: Plastids are covered by a double membrane.

5. **Final Conclusion**:
- Since all three options (nucleus, mitochondria, and plastids) are covered by double membranes, the correct answer is:
- **Option 4: All of the above**.

### Final Answer:
The organelle covered by a double membrane is **Option 4: All of the above** (nucleus, mitochondria, and plastids).

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