Active reabsorption of `Na(+), K^(+)` takes place in

Options

A. DCT
B. PCT
C. Ascending limb of Henle's loop
D. All of these

Answer

To determine where the active reabsorption of sodium (Na⁺) and potassium (K⁺) takes place in the nephron, we need to analyze the different segments of the nephron and their functions.

### Step-by-Step Solution:

1. **Understanding the Nephron Structure**:
- The nephron consists of several parts: Bowman's capsule, Proximal Convoluted Tubule (PCT), Loop of Henle (which includes the descending and ascending limbs), Distal Convoluted Tubule (DCT), and the Collecting Duct.

2. **Identifying the Function of Each Segment**:
- **Proximal Convoluted Tubule (PCT)**: This is where a significant amount of reabsorption occurs. It reabsorbs sodium (Na⁺), potassium (K⁺), water, glucose, and various nutrients back into the bloodstream.
- **Loop of Henle**:
- **Descending Limb**: Primarily reabsorbs water, not sodium or potassium.
- **Ascending Limb**: Reabsorbs sodium (Na⁺) and chloride (Cl⁻) but does not reabsorb potassium (K⁺).
- **Distal Convoluted Tubule (DCT)**: This segment also plays a role in reabsorption and secretion. It reabsorbs sodium (Na⁺) but secretes potassium (K⁺) into the urine.
- **Collecting Duct**: This segment can reabsorb water depending on the body's needs but is not primarily involved in the reabsorption of sodium and potassium.

3. **Conclusion**:
- The active reabsorption of both sodium (Na⁺) and potassium (K⁺) primarily occurs in the **Proximal Convoluted Tubule (PCT)**.

### Final Answer:
The active reabsorption of Na⁺ and K⁺ takes place in the **Proximal Convoluted Tubule (PCT)**.

---