From the medulla of kidney, urea is secreted into the `"_______"`

Options

A. Thick segment of AL of Henle's loop
B. Thin segment of AL of Henle's loop
C. DL of Henle's loop
D. DL of Vasa recta

Answer

To answer the question "From the medulla of kidney, urea is secreted into the '_______'", we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Structure of the Kidney**: The kidney has several parts, including the cortex, medulla, and nephrons. The medulla is the inner region of the kidney.

2. **Identify the Function of the Medulla**: The medulla plays a crucial role in the concentration of urine and the regulation of water and solute balance. It contains structures such as the loops of Henle and the collecting ducts.

3. **Focus on Urea Secretion**: Urea is a waste product formed from the breakdown of proteins. In the kidney, urea is primarily involved in the process of urine formation and is secreted into specific parts of the nephron.

4. **Examine the Options**: The question provides options regarding where urea is secreted from the medulla. The key point to note is that urea is secreted into the thin segment of the ascending limb of the loop of Henle.

5. **Conclusion**: Therefore, the correct answer to the question is that urea is secreted into the **"thin segment of the ascending limb of Henle's loop"**.

### Final Answer:
From the medulla of kidney, urea is secreted into the **"thin segment of the ascending limb of Henle's loop"**.

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