Question

Which part of the human nephron is primarily responsible for the reabsorption of glucose and amino acids?

• A. Bowman’s capsule
• B. Proximal convoluted tubule
• C. Loop of Henle
• D. Distal convoluted tubule

Hint:

In nephron function, associate the proximal convoluted tubule with the reabsorption of most nutrients and water, the loop of Henle with concentration gradients, and the distal tubule with fine-tuning ion balance.

Answer 1

The Correct Option is B

The nephron, the kidney's functional unit for blood filtration and urine production, has the proximal convoluted tubule (PCT) as its main site for reabsorbing glucose, amino acids, and other vital substances from the glomerular filtrate back into circulation. The PCT reabsorbs nearly all glucose and amino acids, alongside approximately 65–80% of water, sodium, and other ions, utilizing both active and passive transport.
The functions of other nephron components are as follows:
- Bowman’s capsule: Encloses the glomerulus and gathers filtrate, but does not significantly reabsorb substances.
- Loop of Henle: Primarily establishes a medullary concentration gradient to aid water and ion reabsorption, not glucose or amino acids.
- Distal convoluted tubule: Manages ion balance (e.g., sodium, potassium, calcium) and pH, with minimal reabsorption of glucose or amino acids.
Consequently, the proximal convoluted tubule is the nephron segment chiefly responsible for glucose and amino acid reabsorption.