MDCAT Biology MCQs

Correct answer A. It is permeable to water but relatively impermeable to salts

Correct answer D. Na⁺ and Cl⁻ are actively transported out while water cannot follow

Correct answer C. Building a high solute concentration in the medulla so that concentrated urine can be produced

Correct answer B. Neurosecretory cells of the hypothalamus

Correct answer A. It makes the distal tubule and collecting duct more permeable to water

Correct answer B. A rise in the solute concentration of blood plasma

Correct answer C. Large volumes of dilute urine

Correct answer B. ADH secretion falls and a large volume of dilute urine is produced

Correct answer A. Adrenal cortex

Correct answer A. Increased reabsorption of Na⁺ and secretion of K⁺ in the distal tubule and collecting duct

Correct answer B. Juxtaglomerular cells

Correct answer A. Renin release → angiotensin II formation → aldosterone secretion → more Na⁺ reabsorbed

Correct answer D. Hydrogen ions and potassium ions

Correct answer C. They have low hydrostatic pressure that favours reabsorption

Correct answer B. Efferent arteriole

Correct answer B. Bowman's capsule → proximal tubule → loop of Henle → distal tubule → collecting duct

Correct answer D. Glomeruli and convoluted tubules

Correct answer B. Collecting urine from the collecting ducts and passing it into the ureter

Correct answer C. 180 L

Correct answer C. 10 mmHg