Glomerular hydrostatic pressure (GHP):

Correct Answer: A

Rationale: Glomerular hydrostatic pressure (GHP), typically around 55 mmHg, is the force exerted by blood pressure within glomerular capillaries, pushing fluid out into the Bowman's capsule during filtration. It's the primary driving force of GFR, opposed by oncotic and capsular pressures. It doesn't push fluid back (B), affect filtration neutrally (C), or alter oncotic pressure (D), making A correct.

Correct Answer: B

Rationale: The fastest system controlling [H⁺] is CO₂ excretion by the lungs, acting within seconds to minutes via increased ventilation, reducing PCO₂ and thus H₂CO₃ (H⁺ source). Buffers (C) act instantly but don't eliminate H⁺, kidney H⁺ excretion (A) takes hours, and carbonic anhydrase (D) is a mechanism, not a system, making B correct.

Correct Answer: B

Rationale: Paternalism (B) occurs when others (e.g., family) assume decision-making authority, believing they know best, overriding patient autonomy. Justice (A) involves fairness, pragmatism (C) practicality, and veracity (D) truthfulness, none of which fit this assumption of control without patient input, making B correct.

Correct Answer: B

Rationale: Erythropoietin (EPO) release by kidney interstitial cells is triggered by low blood oxygen levels (B) (hypoxia), stimulating red blood cell production in bone marrow to improve oxygen delivery. High oxygen (A) or RBCs (C) suppress it, and COâ‚‚ (D) isn't the trigger, making B correct.

Correct Answer: D

Rationale: Solute uptake and oncotic pressure drive water reabsorption (A), Na/H antiports facilitate sodium and water movement (B), and aquaporin-1 enables water flow (C). All are true—solutes and pressure pull water, Na/H links sodium to water, and aquaporins allow passage—making E (all are correct), reassigned as D, correct.