Alcohol is a _______ because it ________ the secretion of ADH.

Correct Answer: B

Rationale: Alcohol is a diuretic inhibits ADH secretion (e.g., hypothalamus suppression), increasing urine. Antidiuretic increases retention opposite. Diuretic/increases ADH contradicts more water retained. Antidiuretic/inhibits misnames diuresis occurs. Diuretic/inhibition distinguishes it, key to alcohol's effect, unlike retention or reverse errors.

Correct Answer: D

Rationale: Vasa recta acts as a countercurrent exchanger maintains medullary gradient (e.g., loops with Loop of Henle). Afferent arterioles supply not exchange. Urethra drains no countercurrent. Trigone is bladder not exchanger. Vasa recta's exchange distinguishes it, critical for concentration, unlike supply or drainage structures.

Correct Answer: B

Rationale: Each H secreted pairs with Na reabsorption e.g., Na /H exchanger in PCT maintains electroneutrality. pH doubling is logarithmic false. Aldosterone isn't directly tied separate control. pH decrease is blood not tubule effect. Na reabsorption distinguishes it, key to ion balance, unlike pH or hormonal errors.

Correct Answer: A

Rationale: Increased cardiac output boosts GFR e.g., more blood pressure (~55 mmHg) at glomerulus. Lower BP decreases GFR opposite. Less fluid reduces volume not GFR directly. Temperature affects skin not kidneys. Cardiac output's effect distinguishes it, key to filtration rate, unlike pressure drop or external factors.

Correct Answer: B

Rationale: Urea clearance = UV/P: U=18.2 mg/mL, V=2 mL/min, P=26 mg/100 mL = 0.26 mg/mL. (18.2 × 2) / 0.26 = 36.4 / 0.26 ≈ 70 mL/min e.g., partial reabsorption. 35 underestimates half off. 105/140 overstate exceed GFR. 70 distinguishes it, critical for clearance calc, unlike wrong values.