The kidney ascends from the pelvis to the upper lumbar region as a result of:

Correct Answer: B

Rationale: Kidney ascent is driven by lumbar/sacral growth not ureteric elongation (forms collecting system), cap migration, or all; 'b' fits best. This explains positional shift, critical for anatomy, contrasting with mechanical or combined causes.

Correct Answer: A

Rationale: Amino acids aren't nitrogenous wastes reabsorbed or metabolized, not excreted (e.g., PCT). Urea, from protein breakdown major waste. Uric acid, from purines excreted. Creatinine, from muscle waste product. Amino acids' conservation distinguishes them, critical for nitrogen reuse, unlike waste products excreted.

Correct Answer: A

Rationale: The hilum is the kidney's depression entry/exit for artery, vein, ureter (e.g., medial notch). Capsule is protective not an opening. Cortex is nephron-rich internal. Pyramid is medullary not entry. Hilum's gateway role distinguishes it, critical for vascular/urinary access, unlike structural zones.

Correct Answer: A

Rationale: Glomeruli are in the cortex cortical nephrons dominate (e.g., filtration zone). Medulla has fewer juxtamedullary. Pelvis collects not filters. Pyramids are medullary subset. Cortex's glomerular density distinguishes it, critical for GFR, unlike deeper or collecting areas.

Correct Answer: A

Rationale: Blood flows: afferent arteriole, glomerulus, efferent arteriole, peritubular capillary e.g., filtration to reabsorption. Peritubular before glomerulus reverses impossible. Efferent first skips input wrong. Peritubular start ignores filtration false. Correct order distinguishes it, key to nephron circulation, unlike reversed sequences.