All of the following are chemical buffer systems, except?

Correct Answer: C

Rationale: Respiratory isn't a chemical buffer physiological via COâ‚‚ excretion (e.g., lungs). Phosphate, bicarbonate, and proteins are chemical bind H directly. Respiratory's physiological role distinguishes it, key to system classification, unlike chemical buffers.

Correct Answer: A

Rationale: Aldosterone retains Na+ and excretes K+ not glucose (insulin), oxygen (lungs), or protein (liver). This specifies electrolyte control, critical for blood pressure, contrasting with unrelated functions.

Correct Answer: B

Rationale: Hematuria is blood in urine not glycosuria (glucose), proteinuria (protein), or anuria (no urine). This terms a key symptom, critical for injury/infection detection, contrasting with other conditions.

Correct Answer: B

Rationale: Urea is the primary nitrogenous waste not glucose (reabsorbed), hemoglobin (RBCs), or protein (filtered). This identifies excretion target, critical for nitrogen balance, contrasting with reabsorbed/blood components.

Correct Answer: B

Rationale: Renal columns of Bertin are cortical tissue between pyramids not medullary rays (cortex to medulla), interlobular cortex (misnomer), or none. This defines cortical extensions, critical for kidney structure, contrasting with medullary or vague terms.