Organelle X bears ribosomes on its outer surface. Organelle X and organelle Y together give rise to organelle Z which is often referred to as 'suicide bag' of cells
Select the incorrect statement regarding X, Y and Z.

Options

A. Organelle X takes part in formation of proteins.
B. Organelle Z is bound by single membrane.
C. Organelle Y is the main site of cellular respiration.
D. Organelle Z is involved in autophagy.

Explanation

To solve the question, we need to identify the organelles X, Y, and Z based on the information provided and then determine which statement about them is incorrect.

### Step-by-Step Solution:

1. **Identify Organelle X**:
- The question states that organelle X bears ribosomes on its outer surface. This description matches the **Rough Endoplasmic Reticulum (RER)**, which is known for having ribosomes attached to its surface, giving it a "rough" appearance. The RER is involved in protein synthesis.

2. **Identify Organelle Y**:
- The question mentions that organelle X and organelle Y together give rise to organelle Z. Based on the context, organelle Y is the **Golgi Apparatus**. The Golgi apparatus processes and packages proteins that are synthesized in the RER.

3. **Identify Organelle Z**:
- Organelle Z is referred to as the "suicide bag" of the cell. This term is commonly used to describe **Lysosomes**, which are involved in breaking down waste materials and cellular debris.

4. **Analyze the Statements**:
- Now we need to evaluate the statements provided:
- **Statement 1**: "Organelle X takes part in the formation of protein."
- This is **correct** as the Rough Endoplasmic Reticulum synthesizes proteins.
- **Statement 2**: "Z is bounded by a single membrane."
- This is also **correct**; lysosomes are surrounded by a single membrane.
- **Statement 3**: "Y is the main site of cellular respiration."
- This statement is **incorrect**. The main site of cellular respiration is the **Mitochondria**, not the Golgi apparatus.
- **Statement 4**: "Z is involved in autophagy."
- This is **correct**; lysosomes play a role in autophagy, the process of degrading and recycling cellular components.

5. **Conclusion**:
- The incorrect statement regarding X, Y, and Z is: "Y is the main site of cellular respiration."

### Final Answer:
The incorrect statement is: "Y is the main site of cellular respiration."