PCT absorbs about 70-80 % electrolytes and water. It is the major site for selective reabsorption. Bowman's capsule consists of cells called podocytes, that have some minute spaces in between which are termed as filtration slits or slit pores. Ultrafiltration occurs through these pores. Loop of Henle maintains the high osmolarity of medullary interstitial fluid by the counter-current mechanism.
Structures responsible for the concentration of urine: 1. Henle's loop 2. Vasa recta.
Functions of DCT - Conditional reabsorption of Na+ and water, reabsorption of HCO3 - and selective secretion of H+,andK+, for maintaining the pH and sodium-potassium balance in the blood.