What happens to the concentration of tubular fluid as it flows up the ascending loop of Henle?
A) Its concentration remains unchanged.
B) Its concentration increases.
C) Its concentration decreases.
D) Its concentration decreases only if ADH is present.

Question

Quizplus · Accepted Answer

As tubular fluid flows up the ascending loop of Henle, the walls of the loop actively transport ions (sodium, chloride, and potassium) out of the tubular fluid and into the interstitial fluid. This creates a concentration gradient, with the interstitial fluid becoming increasingly concentrated with these ions. As a result, the concentration of the tubular fluid decreases as it flows up the ascending loop of Henle. This process is essential for the formation of concentrated urine. The presence of ADH (antidiuretic hormone) can affect this process, but its absence does not prevent the concentration gradient from forming.

What Happens to the Concentration of Tubular Fluid as It