Cu containing respiratory pigment is `:`

Options

A. Haemoglobin
B. Haemocyanin
C. Chlorocruorin
D. All the above

Answer

To solve the question "Cu containing respiratory pigment is:", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Question**: We need to identify which respiratory pigment contains copper (Cu).

2. **Define Respiratory Pigments**: Respiratory pigments are metalloproteins that play a crucial role in the transport of oxygen in the body. They contain metal ions that bind to oxygen.

3. **List Common Respiratory Pigments**: The common respiratory pigments include:
- Hemoglobin
- Hemocyanin
- Hemoerythrin
- Chlorocruorin

4. **Identify the Metal in Each Pigment**:
- **Hemoglobin**: Contains Iron (Fe).
- **Hemoerythrin**: Contains Iron (Fe).
- **Chlorocruorin**: Contains Iron (Fe).
- **Hemocyanin**: Contains Copper (Cu).

5. **Analyze the Options**: From the list, we see that:
- Hemoglobin, Hemoerythrin, and Chlorocruorin all contain Iron.
- Hemocyanin is the only pigment that contains Copper.

6. **Conclusion**: The respiratory pigment that contains copper is **Hemocyanin**.

### Final Answer:
The Cu containing respiratory pigment is **Hemocyanin**.

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