Diameter of the renal afferent vessel is

Options

A. Same as that of efferent
B. Smaller than that of efferent
C. Larger than that of efferent
D. There is no efferent vessel

Answer

To determine the diameter of the renal afferent vessel, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure**: The renal afferent vessel, also known as the afferent arteriole, is responsible for supplying blood to the glomerulus in the kidney.

2. **Compare with Efferent Vessel**: The efferent vessel, or efferent arteriole, carries blood away from the glomerulus. It is important to compare the diameter of the afferent arteriole with that of the efferent arteriole.

3. **Recognize the Diameter Relationship**: The afferent arteriole has a larger diameter than the efferent arteriole. This difference in diameter is crucial for maintaining adequate blood pressure within the glomerulus.

4. **Understand the Implications of Diameter**: The larger diameter of the afferent arteriole allows more blood to enter the glomerulus, creating higher pressure. This pressure is necessary for the process of ultrafiltration, where blood is filtered to form urine.

5. **Conclusion**: Based on the comparison, we conclude that the diameter of the renal afferent vessel is larger than that of the efferent vessel.

### Final Answer:
The diameter of the renal afferent vessel is **larger than that of the efferent vessel**.

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