Organ System Integration and Homeostasis (3B) Practice Test

In a controlled feeding study, participants follow a low-sodium diet for one week. Compared with baseline, plasma renin activity and aldosterone increase, and urinary sodium excretion decreases. Which interaction is critical for maintaining homeostasis in this condition?

A patient is treated with a loop diuretic for edema. Over several days, they develop hypokalemia and mild metabolic alkalosis. Which outcome is most consistent with the given physiological response?