PATHOLOGY

Detailed explanation-1: -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. Sodium reabsorption is tightly coupled to passive water reabsorption, meaning when sodium moves, water follows.

Detailed explanation-2: -While the PCT absorbs 70-80% of the water, the remaining 15-20% is reabsorbed in the DCT. DCT reabsorption with the help of the hormone aldosterone maintains sodium and water levels.

Detailed explanation-3: -Reabsorption of water and specific solutes occurs to varying degrees over the entire length of the renal tubule. Bulk reabsorption, which is not under hormonal control, occurs largely in the proximal tubule. Over 70% the filtrate is reabsorbed here.