Even under the influence of ADH, maximum reabsorption of water occurs in which of the following segments of a nephron?

Options

A. Distal convoluted tubule
B. Collecting duct
C. Loop of Henle
D. Proximal convoluted tubule

Answer

To solve the question regarding the maximum reabsorption of water in the nephron under the influence of ADH (Antidiuretic Hormone), we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of ADH**:
- ADH is a hormone that plays a crucial role in regulating water balance in the body. It promotes water reabsorption in the kidneys, particularly in certain segments of the nephron.

2. **Identify the Segments of the Nephron**:
- The nephron consists of several segments:
- Proximal Convoluted Tubule (PCT)
- Loop of Henle
- Distal Convoluted Tubule (DCT)
- Collecting Duct

3. **Determine Where Maximum Water Reabsorption Occurs**:
- The PCT is primarily responsible for the reabsorption of a significant amount of water, ions, and nutrients.
- The Loop of Henle also plays a role in water reabsorption but is more focused on concentrating urine.
- The DCT and collecting duct are influenced by ADH, which increases water permeability, but they do not account for the maximum water reabsorption.

4. **Conclusion**:
- The segment where maximum reabsorption of water occurs, even under the influence of ADH, is the **Proximal Convoluted Tubule (PCT)**.

### Final Answer:
The maximum reabsorption of water occurs in the **Proximal Convoluted Tubule (PCT)**.

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