In earthworm, haemoglobin is present in

Options

A. Blood corpuscles
B. Both blood corpuscles and plasma
C. Plasma
D. Absent

Answer

**Step-by-Step Solution:**

1. **Understanding Earthworm Anatomy**: Begin by recognizing that the earthworm is a terrestrial invertebrate with a tube body plan. This means it has a long, cylindrical body that is segmented.

2. **Identifying Hemoglobin**: Hemoglobin is a respiratory pigment responsible for transporting oxygen throughout the body. It is crucial for the respiratory process in many organisms.

3. **Blood Composition in Earthworm**: The blood of the earthworm is divided into two main components: plasma and blood corpuscles. The plasma is the liquid component, while blood corpuscles include red blood cells (RBCs), white blood cells (WBCs), and platelets.

4. **Presence of Hemoglobin**: In earthworms, hemoglobin is not found in red blood cells (as they lack RBCs). Instead, it is present in the plasma, which is the liquid part of the blood.

5. **Conclusion**: Therefore, the hemoglobin in earthworms is present in the plasma. The correct answer to the question is that hemoglobin is present in the plasma.

**Final Answer**: In earthworm, hemoglobin is present in the plasma.

---