In which animal blood is red but blood corpuscles are absent?

Options

A. Cockroach
B. Earthworm
C. Birds
D. Bedbug

Answer

**Step-by-Step Solution:**

1. **Understanding the Question**: The question asks for an animal whose blood is red but lacks blood corpuscles (red blood cells).

2. **Analyzing the Options**: The options provided are:
- Cockroach
- Earthworm
- Birds
- Bed bug

3. **Evaluating Each Option**:
- **Cockroach**: Cockroaches have a hemolymph that is not red; it is usually colorless or yellowish due to the absence of hemoglobin.
- **Earthworm**: Earthworms have red blood because they contain hemoglobin, but it is dissolved in the plasma rather than contained in red blood cells (RBCs). Therefore, they do not have traditional blood corpuscles.
- **Birds**: Birds have red blood cells that contain hemoglobin, so their blood is red due to the presence of RBCs.
- **Bed Bug**: Bed bugs also have red blood due to the presence of hemoglobin in their blood cells.

4. **Conclusion**: The only animal from the options provided that has red blood but lacks red blood corpuscles is the **Earthworm**.

5. **Final Answer**: The answer is **Earthworm**.

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