A 56-year-old patient with severe shock has glomerular hydrostatic pressure of 30 mmHg, oncotic pressure of 25 mmHg, capsular hydrostatic pressure of 15 mmHg. Calculate the Net Filtration Pressure.

Correct Answer: C

Rationale: Net Filtration Pressure (NFP) = glomerular hydrostatic pressure (HPG) - (oncotic pressure [OPG] + capsular hydrostatic pressure [HPC]): 30 - (25 + 15) = -10 mmHg. Positive 10 mmHg ignores opposition incorrect. Zero miscalculates balance. 5 mmHg underestimates opposition. Negative NFP distinguishes it, indicating no filtration due to shock (e.g., low HPG), key to GFR collapse, unlike positive or neutral errors.

Correct Answer: D

Rationale: Erythropoietin is a kidney-made protein produced by peritubular cells (e.g., hypoxia-driven anemia correction). Angiotensin is from angiotensinogen liver, converted renally. Mesangial matrix is structural not protein. Creatinine is muscle waste not synthesized. Erythropoietin's renal origin distinguishes it, key to hematopoiesis, unlike precursors, structures, or wastes.

Correct Answer: C

Rationale: Urine excretion is the elimination of substances via urine final output (e.g., waste removal). Secretion adds to urine specific process. Reabsorption conserves opposite. Filtration starts not eliminates. Excretion's end role distinguishes it, key to renal clearance, unlike process-specific terms.

Correct Answer: A

Rationale: First micturition reflex stimulation is at 150 mL initial urge from stretch (e.g., afferent signal). 300 mL is fullness later. 400 mL discomfort escalated. 560 mL exceeds typical late. Early trigger distinguishes it, critical for reflex onset, unlike higher volumes.

Correct Answer: C

Rationale: Peptides are reabsorbed via endocytosis PCT engulfs small proteins (e.g., filtered peptides), energy-dependent. Facilitated diffusion suits glucose not peptides. Active transport is Na not engulfing. Passive diffusion lacks mechanism insufficient. Endocytosis distinguishes it, critical for protein recovery, unlike diffusion or pump methods.