Pulmonary artery differs from pulmonary vein in having

Options

A. (a) no endothelium
B. (b) having strong valves
C. (c) having oxygenated blood
D. (d) having thick muscular walls

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks how the pulmonary artery differs from the pulmonary vein. We need to identify the key differences between these two blood vessels.

2. **Identify Blood Type**: The pulmonary artery carries deoxygenated blood from the right ventricle of the heart to the lungs. In contrast, the pulmonary vein carries oxygenated blood from the lungs to the left atrium of the heart.

3. **Wall Thickness**: The pulmonary artery has thick muscular walls. This is necessary because it needs to withstand the high pressure of the blood being pumped from the heart. On the other hand, the pulmonary vein has thinner walls since it operates under lower pressure.

4. **Lumen Size**: The pulmonary artery has a narrow lumen, which helps maintain high pressure. In contrast, the pulmonary vein has a wider lumen.

5. **Presence of Valves**: The pulmonary artery does not have valves, while the pulmonary vein contains valves that prevent the backflow of blood.

6. **Endothelium**: Both the pulmonary artery and vein have an endothelium lining, which is a common feature.

7. **Conclusion**: Based on these differences, the pulmonary artery differs from the pulmonary vein primarily in having thick muscular walls.

### Final Answer:
The pulmonary artery differs from the pulmonary vein in having thick muscular walls.

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