Which blood corpuscle is largest in diameter ?

Options

A. Erythrocyte
B. Monocyte
C. Neutrophil
D. Lymphocyte.

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Corpuscles**: Blood corpuscles are the cells found in blood, which include red blood cells (erythrocytes) and white blood cells (leukocytes). The question asks for the largest blood corpuscle by diameter.

2. **Analyzing the Options**:
- **Erythrocytes (Red Blood Cells)**: These cells are responsible for transporting oxygen and carbon dioxide. Their diameter is approximately 6.5 to 7 micrometers.
- **Monocytes**: These are a type of white blood cell involved in phagocytosis. Their diameter is around 20 micrometers.
- **Neutrophils**: Another type of white blood cell that also participates in phagocytosis. Their diameter ranges from 12 to 14 micrometers.
- **Lymphocytes**: These cells are crucial for immune responses, with diameters varying from 7 to 10 micrometers or 10 to 14 micrometers.

3. **Comparing Diameters**:
- Erythrocytes: 6.5 to 7 micrometers
- Monocytes: 20 micrometers
- Neutrophils: 12 to 14 micrometers
- Lymphocytes: 7 to 14 micrometers

4. **Identifying the Largest**: Among the diameters listed, monocytes have the largest diameter at 20 micrometers.

5. **Conclusion**: Therefore, the blood corpuscle with the largest diameter is the **monocyte**.

**Final Answer**: Monocytes are the largest blood corpuscles in diameter.

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