Secretion of molecules is higher in which segment of the nephron?

Correct Answer: D

Rationale: The distal convoluted tubule has higher secretion e.g., H , K (fine-tuning) vs. proximal's organic focus (e.g., creatinine). Proximal secretes reabsorption dominates. Thin ascending/descending focus on concentration not secretion. Distal's secretion role distinguishes it, key to ion regulation, unlike proximal or loop priorities.

Correct Answer: B

Rationale: Moistening mouth/throat mucosa inhibits thirst signals hydration (e.g., sensory feedback). Stomach/intestinal stretch activates opposite. Both miscombine stretch stimulates. None ignores mucosa false. Mucosal relief distinguishes it, key to thirst cessation, unlike stretch or null options.

Correct Answer: A

Rationale: Rising [H ] lowers pH acidosis (e.g., pH = -log[H ]). pH increase is alkalosis opposite. Increased pH with acidosis contradicts false. Fallen pH with alkalosis reverses incorrect. Acidosis link distinguishes it, key to pH definition, unlike reversed or mixed errors.

Correct Answer: D

Rationale: Compensated metabolic alkalosis shows high PCO₂ (hypoventilation), high HCO₃⁻ (primary), high pH lungs retain CO₂ to offset (e.g., vomiting). Low PCO₂ is uncompensated acute. Low HCO₃⁻/pH is acidosis opposite. High PCO₂/low pH is respiratory acidosis unrelated. Compensation distinguishes it, key to acid-base balance, unlike uncompensated or opposite states.

Correct Answer: C

Rationale: The glomerulus filters blood into Bowman's capsule not loop of Henle (reabsorption), ureter (transport), or collecting duct (concentration). This pinpoints filtration site, critical for GFR, contrasting with later nephron segments.