Which of the following structures is present in the male urethra but is NOT present in the female urethra

Correct Answer: B

Rationale: Male urethra has transitional epithelium near bladder (not typical in female) glands of Littre and squamous are in both. This corrects gender difference, key for urology, contrasting with shared features.

Correct Answer: A

Rationale: Pronephros forms in the cervical region of intermediate mesoderm not thoracic, lumbar, sacral, or combined. This transient structure (week 4) regresses in humans, giving way to mesonephros. Its cranial location reflects early embryonic patterning, key for understanding nephric succession, contrasting with caudal regions.

Correct Answer: C

Rationale: Ureteric bud sprouts from the mesonephric duct not urogenital sinus, vesicourethral canal, paramesonephric duct, or cloaca. This origin drives metanephric induction, key for kidney formation, contrasting with unrelated structures.

Correct Answer: D

Rationale: Bladder forms from vesicourethral canal (body), allantois (apex), and mesonephric ducts (trigone) all apply. 'All' captures full origin, key for anatomy, contrasting with partial selections.

Correct Answer: B

Rationale: Kidneys maintain acid-base balance by excreting H and reabsorbing HCO₃⁻ e.g., PCT reclaims HCO₃⁻, distal tubule secretes H . Excreting both loses buffer acidosis risk. Reabsorbing H /excreting HCO₃⁻ reverses alkalosis. Reabsorbing both retains acid imbalanced. H excretion/HCO₃⁻ retention distinguishes it, key to pH regulation, unlike dual loss or retention.