Oxygen-carrying respiratory pigment of cockroach and other insect is

Options

A. Hemoglobin
B. Hemocyanin
C. Hemoerythrin
D. None

Answer

To answer the question "What is the oxygen-carrying respiratory pigment of cockroach and other insects?", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Circulatory System of Cockroach**:
- Cockroaches have an open circulatory system that includes a heart, vessels, and hemolymph. Hemolymph is the fluid that circulates within this system.

2. **Identify the Components of Hemolymph**:
- Hemolymph consists of plasma and hemocytes (blood cells). It plays a crucial role in transporting nutrients and gases throughout the cockroach's body.

3. **Consider the Options for Respiratory Pigments**:
- The question provides several options for the respiratory pigment. We will evaluate each one.

4. **Evaluate Hemoglobin**:
- Hemoglobin is a red-colored respiratory pigment found in humans and other vertebrates. Since cockroaches are not vertebrates, hemoglobin is not present in them. Therefore, this option is incorrect.

5. **Evaluate Hemocyanin**:
- Hemocyanin is a copper-containing respiratory pigment found in many invertebrates, including arthropods like cockroaches. It is responsible for transporting oxygen in these organisms. Thus, this option is correct.

6. **Evaluate Hemoerythrin**:
- Hemoerythrin is an oligomeric protein that transports oxygen in marine invertebrates. Since cockroaches are terrestrial and not marine organisms, they do not contain hemoerythrin. Therefore, this option is also incorrect.

7. **Conclusion**:
- Based on the evaluations, the correct answer is that the oxygen-carrying respiratory pigment of cockroach and other insects is **hemocyanin**.

### Final Answer:
The oxygen-carrying respiratory pigment of cockroach and other insects is **hemocyanin**.