The selective reabsorption of glucose and amon acids into the blood takes place mainly in :
(a) Proximal convoluted tubule
(b) Henle's loop
(c) Distal convoluted tubules
(d) Collecting duct

Options

A. Proximal convoluted tubule
B. Henle's loop
C. Distal convoluted tubules
D. Collecting duct

Answer

To solve the question regarding where the selective reabsorption of glucose and amino acids into the blood takes place, we can follow these steps:

### Step 1: Understand the Question
The question asks about the specific location in the nephron where glucose and amino acids are selectively reabsorbed back into the bloodstream.

### Step 2: Identify the Options
The options provided are:
(a) Proximal convoluted tubule (PCT)
(b) Henle's loop
(c) Distal convoluted tubule (DCT)
(d) Collecting duct

### Step 3: Recall the Function of Each Nephron Segment
- **Proximal Convoluted Tubule (PCT)**: This is where a significant amount of reabsorption occurs, including glucose and amino acids.
- **Henle's Loop**: Primarily involved in the concentration of urine and does not reabsorb glucose or amino acids.
- **Distal Convoluted Tubule (DCT)**: Involved in the reabsorption of ions and water but not primarily glucose or amino acids.
- **Collecting Duct**: Mainly involved in the final concentration of urine and water reabsorption, not glucose or amino acids.

### Step 4: Analyze the Role of the PCT
The PCT contains specialized transport mechanisms, such as symporters, that actively transport glucose and amino acids from the tubular fluid back into the blood. This process is energy-dependent and is crucial for maintaining nutrient levels in the body.

### Step 5: Conclusion
Based on the analysis, the correct answer is:
**(a) Proximal convoluted tubule**