NEET PG DENTAL EXAM

Detailed explanation-1: -The descending limb is highly permeable to water, with reabsorption occurring passively via aquaporin-1 (AQP1) channels. Small amounts of urea, sodium (Na+) and other ions are also reabsorbed.

Detailed explanation-2: -Thick ascending limbs of Henle’s loop have at least three major roles: (1) They reabsorb sodium chloride which dilutes the urine.

Detailed explanation-3: -The descending portion of the loop of Henle is extremely permeable to water and is less permeable to ions, therefore water is easily reabsorbed here and solutes are not readily reabsorbed.

Detailed explanation-4: -The descending limb of the loop of Henle is permeable to water but impermeable to electrolytes and this concentrates the filtrate as water moves out from the limb as the filtrate moves down. Whereas the ascending limb is impermeable to water but permeable to electrolytes, this dilutes the filtrate as it moves upward.