Which one of the following has elastic wall ?

Options

A. Precaval
B. Postcaval
C. Dorsal aorta
D. Pulmonary vein

Answer

To determine which of the given options has an elastic wall, let's analyze each option step by step.

### Step 1: Understand the Types of Blood Vessels
Blood vessels are classified into three main types: arteries, veins, and capillaries. Each type has distinct characteristics based on their function and the pressure of the blood they carry.

### Step 2: Identify the Function of Arteries and Veins
- **Arteries**: These vessels carry oxygen-rich blood away from the heart. They need to withstand high pressure, which is why they have thick, elastic walls that can expand and contract.
- **Veins**: These vessels carry carbon dioxide-rich blood back to the heart. They operate under lower pressure compared to arteries, so their walls are thinner and less elastic.

### Step 3: Analyze the Options
1. **Pre-cable**: This is a vein, which means it has a thinner wall and is not elastic.
2. **Post-cable**: This is also a vein, similar to the pre-cable, with a non-elastic wall.
3. **Dorsal Aorta**: This is an artery. As mentioned earlier, arteries have elastic walls to handle high blood pressure.
4. **Pulmonary Vein**: This is a vein that carries oxygenated blood from the lungs to the heart, and like other veins, it has a non-elastic wall.

### Step 4: Conclusion
From the analysis, the only option with an elastic wall is the **Dorsal Aorta**, which is an artery.

### Final Answer
The correct answer is **Dorsal Aorta**.

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