If the afferent arterole diameter is less than effect arteriole then what will happen ?

Options

A. No effect
B. Ultrafiltration reaction is slow .
C. Ultrafiltration is not possible .
D. Ultrafiltration will stop & tubular secretion is start

Answer

**Step-by-Step Solution:**

1. **Understanding the Structure**: The kidneys filter blood through a structure called the nephron, which includes the glomerulus. Blood enters the glomerulus through the afferent arteriole and exits through the efferent arteriole.

2. **Role of Afferent and Efferent Arterioles**: The afferent arteriole brings blood into the glomerulus, while the efferent arteriole carries blood away from it. The diameter of these arterioles affects the pressure within the glomerulus.

3. **Pressure and Filtration**: The filtration process in the kidneys relies on the pressure within the glomerulus. A wider efferent arteriole allows for greater pressure to build up in the glomerulus, facilitating ultrafiltration.

4. **Analyzing the Given Condition**: If the diameter of the afferent arteriole is less than that of the efferent arteriole, it means that less blood is entering the glomerulus compared to what is leaving. This results in lower pressure in the glomerulus.

5. **Conclusion**: With reduced pressure in the glomerulus due to the smaller diameter of the afferent arteriole, ultrafiltration will not occur effectively. Therefore, the correct answer is that ultrafiltration will not be possible.

**Final Answer**: C) Ultrafiltration will not be possible.

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