Question

T/F: The juxtamedullary apparatus acts as a special vascular system called the countercurrent exchanger.

Answer 1

The loop of Henle acts as a countercurrent multiplier, while the vasa recta acts as a countercurrent exchanger.

Step-by-step explanation:

In the loop of Henle, the permeability of the membrane changes. The descending limb is permeable to water, not solutes; the opposite is true for the ascending limb. Additionally, the loop of Henle invades the renal medulla, which is naturally high in salt concentration and tends to absorb water from the renal tubule and concentrate the filtrate. The osmotic gradient increases as it moves deeper into the medulla. Because two sides of the loop of Henle perform opposing functions, as illustrated in Figure 41.8, it acts as a countercurrent multiplier. The vasa recta around it acts as the countercurrent exchanger.