Which hormone does the kidney produce that stimulates red blood cell production?

Correct Answer: C

Rationale: Erythropoietin (EPO) from kidneys boosts RBCs not thrombopoietin, vitamin D, or renin. This specifies hematopoietic role, key for anemia, contrasting with other hormones.

Correct Answer: B

Rationale: ADH increases water reabsorption in DCT/collecting duct not decreasing, diluting, or increasing volume. This defines antidiuretic action, key for concentration, contrasting with diuretic effects.

Correct Answer: A

Rationale: PCT removal halts ~65% reabsorption, stopping urine formation not unaffected, concentrated, or diluted. This underscores PCT role, critical for processing, contrasting with later adjustments.

Correct Answer: B

Rationale: Juxtaglomerular cells in the JGA act as mechanoreceptors sense afferent arteriole pressure (e.g., stretch), releasing renin to adjust GFR. Macula densa cells are chemoreceptors monitor NaCl, not pressure. Intercalated cells (collecting duct) manage acid-base no JGA role. Principal cells (collecting duct) handle water/Na unrelated. Juxtaglomerular cells' pressure-sensing distinguishes them, critical for autoregulation, unlike chemical or distant tubular cells.

Correct Answer: C

Rationale: A -10 mmHg NFP means no filtration forces opposing (oncotic + capsular, 40 mmHg) exceed driving force (hydrostatic, 30 mmHg), halting GFR (e.g., shock). Normal filtration needs positive NFP (~10 mmHg). Increased filtration requires higher positive e.g., hypertension. High reabsorption is tubular not glomerular. Lack of filtration distinguishes it, critical for acute renal failure risk, unlike normal or enhanced filtration.