The countercurrent mechanism in the nephron
A)creates a highly concentrated interstitial fluid so that urine can be concentrated by the collecting ducts when they are permeable to water.
B)is a method to move sodium to control its concentration.
C)keeps the volume of water lost in the urine relatively constant.
D)keeps interstitial fluid hydrated to maintain blood pressure.

Question

Quizplus · Accepted Answer

The countercurrent mechanism in the nephron creates a highly concentrated interstitial fluid by establishing a gradient of solute concentration along the ascending and descending limbs of the loop of Henle. This gradient enables the nephron to produce urine that is more concentrated than the interstitial fluid, which facilitates water reabsorption in the collecting ducts when they become permeable to water. This mechanism is essential for maintaining water balance in the body, especially in arid conditions when water intake is limited.

The Countercurrent Mechanism in the Nephron