From this part urea can be reabsorbed into interstitium to maintain osmolarity of that region

Options

A. PCT
B. DCT
C. loop of Henle
D. collecting duct

Answer

### Step-by-Step Solution:

1. **Understanding the Question**: The question asks about the specific part of the kidney where urea is reabsorbed into the interstitium to help maintain osmolarity.

2. **Identifying Urea Reabsorption**: In the kidneys, urea is a waste product that is filtered out of the blood. However, some of it is reabsorbed back into the body to help maintain osmotic balance.

3. **Locating the Area of Reabsorption**: The primary area in the kidney responsible for the reabsorption of urea is the collecting duct. This duct plays a crucial role in the final concentration of urine and the regulation of water and solutes.

4. **Function of the Collecting Duct**: The collecting duct allows for the reabsorption of urea into the interstitium. This process is essential for maintaining the osmolarity of the renal medulla, which is important for the kidney's ability to concentrate urine.

5. **Conclusion**: Therefore, the correct answer to the question is that urea is reabsorbed into the interstitium from the **collecting duct**.

### Final Answer:
The area from which urea can be reabsorbed into the interstitium to maintain osmolarity is the **collecting duct**.

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