Physiological chemistry (buffers): What is the principal buffer system of human blood that maintains pH near 7.4? Identify the conjugate acid–base pair predominantly responsible for buffering. Choose the correct option.

Q: Physiological chemistry (buffers): What is the principal buffer system of human blood that maintains pH near 7.4? Identify the conjugate acid–base pair predominantly responsible for buffering. Choose the correct option.

Concept/Approach The primary blood buffer is the bicarbonate system: carbonic acid (H₂CO₃) / bicarbonate (HCO₃⁻), regulated by lungs (CO₂) and kidneys (HCO₃⁻). Final Answer H₂CO₃ / HCO₃⁻

Difficulty: Easy

H₂CO₃ / HCO₃⁻
H₂CO₃ / CO₃²⁻
CH₃COOH / CH₃COO⁻
NH₂CONH₂ / NH₂CONH⁺

Correct Answer: H₂CO₃ / HCO₃⁻

Explanation:

Concept/Approach
The primary blood buffer is the bicarbonate system: carbonic acid (H₂CO₃) / bicarbonate (HCO₃⁻), regulated by lungs (CO₂) and kidneys (HCO₃⁻).

Final Answer
H₂CO₃ / HCO₃⁻

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