What is the function of Proximal Convoluted Tubule (PCT) in urine formation?
What is the function of Proximal Convoluted Tubule (PCT) in urine formation?
Maintenance of high osmolarity of medullary interstitial fluid
Reabsorption of essential nutrients, electrolytes and water
Conditional reabsorption of Na⁺ and water
Maintenance of pH and ionic balance of body fluids
Solution
The PCT is lined by simple cuboidal brush border epithelium, which increases the surface area for reabsorption. Nearly all of the essential nutrients and 70-80% of electrolytes and water are reabsorbed by this segment, and it helps to maintain the pH and ionic balance of the body fluids by selective secretion of hydrogen ions and ammonia into the filtrate and by absorbing HCO₃⁻ from it.