Respiratory pigment in cockroach is

Options

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

Answer

**Step-by-Step Solution:**

1. **Identify the Organism**: The question asks about the respiratory pigment in cockroaches, which are classified under the phylum Arthropoda.

2. **Understand Blood Composition in Cockroaches**: In arthropods like cockroaches, the blood is referred to as hemolymph. Unlike vertebrates, hemolymph is a colorless fluid.

3. **Determine the Presence of Respiratory Pigments**: Respiratory pigments are proteins that carry oxygen in the blood. In cockroaches, hemolymph does not contain traditional blood cells or respiratory pigments.

4. **Evaluate Options**:
- **Hemoglobin**: This is a red pigment found in vertebrates, including humans, and is not present in cockroaches.
- **Hemocyanin**: This is a blue pigment found in some arthropods and mollusks, but cockroaches do not have hemocyanin; their hemolymph remains colorless.
- **Hemerythrin**: This is another respiratory pigment found in some invertebrates, but it is not responsible for oxygen transport in cockroaches.

5. **Conclusion**: Since cockroaches do not possess any of the mentioned respiratory pigments, the answer is that cockroaches lack a respiratory pigment.

**Final Answer**: The respiratory pigment in cockroach is none of these.

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