Question

The area of the loop of henle that is most freely permeable to water but impermeable to NaCl is?

1) Ascending limb
2) Descending limb
3) Thin segment
4) Thick segment

Answer 1

The thick portion of the ascending limb is impermeable to water but actively reabsorbs ions.

Step-by-step explanation:

The loop of Henle consists of two sections: thick and thin descending and thin and thick ascending sections. The descending limb of the loop of Henle is impermeable to water, so the water flows from the filtrate to the interstitial fluid. The ascending limb, specifically the thick portion, is completely impermeable to water but actively reabsorbs ions, mainly Na+ and Cl-, through a cotransport system.