The total number of orifices for outgoing and incoming of urine through the bladder is

Correct Answer: B

Rationale: Bladder has 3 orifices: 2 ureters (in), 1 urethra (out) not 2, 4, or 5. This counts openings, vital for anatomy, contrasting with miscounts.

Correct Answer: B

Rationale: Prostaglandin F causes renal vasoconstriction reduces renal blood flow (RBF) and GFR (e.g., opposes vasodilators). Vasodilation (e.g., PGE/I) increases GFR opposite. Renin release is JGA-driven not direct. No effect ignores its role. Constriction's GFR drop distinguishes it, critical for prostaglandin balance, unlike dilation or neutral effects.

Correct Answer: B

Rationale: At 150-300 mL, the bladder triggers the first urge to void stretch receptors signal (e.g., micturition reflex onset). Fullness comes at 300-400 mL escalation. Discomfort at 400-600 mL stronger stretch. Pain at 600-700 mL overdistension. Initial urge distinguishes it, critical for normal voiding cues, unlike later sensations.

Correct Answer: D

Rationale: 1% of GFR is excreted ~180 L/day filtered, ~1.8 L urine (e.g., 99% reabsorbed). 99% excreted reverses impossible. 1% reabsorbed understates most returns. 50% reabsorbed halves reality too low. Low excretion distinguishes it, critical for renal efficiency, unlike reversed or understated options.

Correct Answer: D

Rationale: A GFR marker (e.g., inulin) shouldn't be metabolized must stay intact for clearance (e.g., excreted fully). Not secreted ensures filtration-only true. Not reabsorbed keeps GFR accurate correct. Non-toxic is essential safety. Metabolism distinguishes the error, critical for marker purity, unlike filtration-only criteria.