Question

The ascending limb of loop of Henle is permeable to

• A. Glucose
• B. $N{H}_3$
• C. $N{a}^{+}$
• D. Water

Answer 1

Answer: (C)

$N{a}^{+}$

Ascending limb of the loop of Henle is less permeable to water and more permeable to sodium and chloride ions. As a result of the sodium-potassium ATPase pumps, sodium ions are extracted from the filtrate and replaced in the filtrate by potassium ions. The sodium and chloride ions enter the interstitial fluid of the medulla and from there into the venous capillary drainage and are returned to the systemic circulation.Thus, the correct answer is option C.