Respratory pigment in insects is

Options

A. haemoglobin
B. cytochrome
C. haemocyanin
D. none

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks for the respiratory pigment found in insects. Respiratory pigments are molecules that transport oxygen in the blood or hemolymph of animals.

2. **Evaluating the Options**: The options provided are:
- Hemoglobin
- Cytochrome
- Hemocyanin
- None of these

3. **Analyzing Each Option**:
- **Hemoglobin**: This is a well-known respiratory pigment found in vertebrates, particularly in mammals, birds, and some other animals. It contains iron and is responsible for the red color of blood.
- **Cytochrome**: This is not a respiratory pigment in the traditional sense. Instead, it is a protein involved in electron transport and redox reactions within cells.
- **Hemocyanin**: This is a copper-containing respiratory pigment found in many arthropods, including insects. It is colorless when deoxygenated and turns blue when it binds to oxygen.
- **None of these**: This option implies that none of the previous options are correct.

4. **Identifying the Correct Answer**: Based on the analysis, hemocyanin is the correct respiratory pigment in insects. It is distinct from hemoglobin and is specifically adapted for oxygen transport in the hemolymph of arthropods.

5. **Conclusion**: The respiratory pigment in insects is **hemocyanin**.