Ph, Buffers & Henderson–Hasselbalch MCQ Quiz | Acid–Base & Renal

Welcome to this specialized quiz on pH, Buffers, and the Henderson-Hasselbalch equation, a cornerstone of acid-base physiology for MBBS students. This quiz is designed to test your understanding of the fundamental mechanisms that maintain pH homeostasis in the human body. You will encounter 25 multiple-choice questions covering the major physiological buffer systems, the clinical application of the Henderson-Hasselbalch equation, and the integrated roles of the renal and respiratory systems in regulating acid-base balance. Challenge your knowledge and solidify your concepts. After submitting your answers, you will receive your score and see a detailed breakdown of correct and incorrect responses. You can also download all questions with their correct answers in a PDF format for future revision. Good luck!

1. The Henderson-Hasselbalch equation is crucial for understanding acid-base balance. Which of the following correctly represents it for the bicarbonate buffer system?

2. What is the most important extracellular fluid (ECF) buffer system in the human body?

3. A buffer is most effective when the pH is equal to its pKa. The pKa for the bicarbonate buffer system is 6.1. Why is it so effective at a physiological pH of 7.4?

4. In a patient with metabolic acidosis, what is the expected compensatory response?

5. The phosphate buffer system (H2PO4-/HPO42-) is a major buffer in which of the following compartments?

6. The buffering capacity of hemoglobin is primarily due to which amino acid residue?

7. According to the Henderson-Hasselbalch equation, if the ratio of [HCO3-] to dissolved CO2 ([H2CO3]) in blood increases, what is the effect on blood pH?

8. The enzyme carbonic anhydrase plays a vital role in acid-base balance by catalyzing which reaction?

9. In a state of respiratory acidosis, which of the following is the primary disturbance?

10. The isohydric principle states that:

11. The kidneys regulate acid-base balance long-term. Which of the following is NOT a primary renal mechanism for this regulation?

12. What is the normal ratio of [HCO3-] to dissolved CO2 ([H2CO3]) required to maintain a blood pH of 7.4?

13. The term “pKa” represents:

14. Most of the H+ ions generated from CO2 in tissues are buffered within red blood cells by:

15. The “chloride shift” (Hamburger phenomenon) facilitates the transport of:

16. An ABG report shows pH = 7.25, pCO2 = 55 mmHg, HCO3- = 26 mEq/L. This indicates:

17. Adding a strong acid like HCl to a solution buffered by the bicarbonate system will result in:

18. A patient with uncontrolled diabetes mellitus is likely to have which acid-base disorder?

19. The isoelectric point (pI) of an amino acid is the pH at which:

20. In the renal tubules, the generation of “new” bicarbonate is most closely associated with the excretion of which substance?

21. Deoxyhemoglobin is a better proton acceptor (weaker acid) than oxyhemoglobin. This property is known as the:

22. If a patient’s blood pH is 7.5, pCO2 is 40 mmHg, and [HCO3-] is 32 mEq/L, what is the primary acid-base disturbance?

23. The normal pH range of arterial blood is tightly regulated between:

24. What is the main form in which CO2 is transported in the blood?

25. A patient with severe diarrhea loses a large amount of bicarbonate-rich fluid. This is likely to cause: