Which of the following cells secretes renin?

Correct Answer: C

Rationale: Juxtaglomerular (JG) cells secrete renin e.g., JGA responds to low BP. Macula densa senses NaCl signals JG, doesn't secrete. Glomerular epithelial (podocytes) filter not secrete. Basement membrane is structural not cellular. JG's renin role distinguishes it, key to RAAS, unlike sensing or structural parts.

Correct Answer: B

Rationale: Cl⁻ reabsorption follows Na electrostatic attraction (e.g., PCT Na /Cl⁻ cotransport). Aldosterone boosts Na indirectly Cl⁻, not permeability. Ca² retention is separate unrelated. Osmotic gradient drives water not Cl⁻ directly. Na attraction distinguishes it, critical for electroneutrality, unlike hormonal or osmotic drivers.

Correct Answer: C

Rationale: Macula densa is in the distal tubule senses NaCl, signals JGA (e.g., renin regulation). Proximal tubule reabsorbs not senses. Afferent arteriole supplies not tubular. Efferent is post-glomerular unrelated. Distal location distinguishes it, key to feedback, unlike proximal or vascular parts.

Correct Answer: A

Rationale: Ureter is the tube from kidney to bladder e.g., peristalsis delivers urine. Vasa recta is capillaries not tube. Hypothalamus makes ADH not ureter. Micturition is voiding not structure. Transport role distinguishes it, key to urinary flow, unlike capillaries or actions.