There is increase in blood urea when there is insufficient filtration in

Options

A. loop of Henle
B. distal tubule
C. Bowman’s capsule
D. collecting tubule

Answer

To solve the question regarding the increase in blood urea due to insufficient filtration, we can break down the process step by step:

### Step-by-Step Solution:

1. **Understanding Blood Urea and Filtration**:
- Blood urea is a waste product formed from the breakdown of proteins. Its concentration in the blood can indicate how well the kidneys are functioning, particularly in filtering waste.

2. **Identifying the Site of Filtration**:
- The kidneys filter blood through a structure called the nephron. Within the nephron, the initial filtration occurs in the **Bowman's capsule**. This is where blood is filtered to form urine.

3. **Role of Bowman's Capsule**:
- The Bowman's capsule surrounds a network of capillaries known as the glomerulus. Blood enters the glomerulus under high pressure, which facilitates the filtration process.

4. **Process of Ultrafiltration**:
- During ultrafiltration, small molecules such as urea, glucose, and salts pass through the capillary walls into the Bowman's capsule, while larger molecules like proteins and blood cells remain in the bloodstream.

5. **Consequences of Insufficient Filtration**:
- If there is insufficient filtration occurring in the Bowman's capsule, the small waste products, including urea, are not adequately removed from the blood. This leads to an increase in blood urea concentration.

6. **Conclusion**:
- Therefore, the correct answer to the question is that an increase in blood urea occurs when there is insufficient filtration in the **Bowman's capsule**.

### Final Answer:
**Bowman's capsule**

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