Basically, what occurs in the countercurrent multiplier process?
A) Sodium is pumped into the blood while potassium is actively transported out of the blood back into the tissues.
B) A higher sodium concentration is produced in the renal medulla that osmotically draws out water, reducing it within the tubules and the urine.
C) Glucose and sodium are cotransported from urine back into blood.
D) Creatinine is actively transported out of the blood into urine.
E) Uric acid is excreted into the kidney tubules while urea is reabsorbed in the nephron loop.

Question

Quizplus · Accepted Answer

The countercurrent multiplier process involves the establishment of a concentration gradient of salt (NaCl) in the renal medulla. This is accomplished by the active transport of sodium ions from the ascending limb of the loop of Henle into the surrounding interstitial fluid. The ascending limb of the loop is impermeable to water, so as the NaCl is removed, the filtrate within the tubule becomes more dilute. This sets up a gradient that allows the passive reabsorption of water from the descending limb of the loop as it passes through the more concentrated medulla. This water reabsorption concentrates the urine, which is important for conserving water in the body. Thus, choice B is the correct answer.

Basically, What Occurs in the Countercurrent Multiplier Process