ANATOMY

Detailed explanation-1: -Proximal tubules are responsible for reabsorbing approximately 65% of filtered load and most, if not all, of filtered amino acids, glucose, solutes, and low molecular weight proteins.

Detailed explanation-2: -Most of the solute reabsorbed in the proximal tubule is in the form of sodium bicarbonate and sodium chloride, and about 70% of the sodium reabsorption occurs here.

Detailed explanation-3: -As much as 60%–70% of total Na reabsorption takes place along the proximal convoluted tubule (PCT) and proximal straight tubule, and because reabsorption is near isotonic in this part of the nephron, this is also true for the reabsorption of water.

Detailed explanation-4: -Proximal convoluted tubule is involved in selective reabsorption of glucose, amino acids, salt and water ino peritubular capillary network. Glucose, amino acids and salts are actively reabsorbed while water reabsorption is a passive process.

Detailed explanation-5: -The main function of the PCT is to reabsorb water and solutes like sodium, which is continuously pumped into the interstitium to create a gradient that allows many other solutes and even water to be reabsorbed by tubule cells.