Of the following, the one which is an example of buffer system in
blood is

Options

A. Albumin and globulin
B. Oxygen and carbon dioxide
C. Oxygen and carbon monoxide
D. Sodium bicarbonate and carbonic acid

Answer

**Step-by-Step Solution:**

1. **Understanding Buffer Systems**: A buffer system in blood is crucial for maintaining the acid-base balance. It helps to stabilize the pH of blood within a narrow range, typically between 7.35 and 7.45.

2. **Identifying Components of the Buffer System**: The primary buffer system in human blood involves carbonic acid (H2CO3) and bicarbonate ions (HCO3-). The enzyme carbonic anhydrase facilitates the reaction between carbon dioxide (CO2) and water (H2O) to form carbonic acid.

3. **Dissociation of Carbonic Acid**: Carbonic acid can dissociate into bicarbonate ions and hydrogen ions. This dissociation is essential for the buffer system, as it allows the blood to neutralize excess acids or bases.

4. **Evaluating the Options**: The question provides four options:
- Option 1: Albumin and globulin (incorrect, as these are proteins and not part of the buffer system).
- Option 2: Oxygen and carbon dioxide (incorrect, as these are gases involved in respiration, not buffering).
- Option 3: Oxygen and carbon monoxide (incorrect, as carbon monoxide is not part of the normal respiratory process).
- Option 4: Sodium bicarbonate and carbonic acid (correct, as this is the actual buffer system in blood).

5. **Conclusion**: Based on the evaluation of the options, the correct answer is sodium bicarbonate and carbonic acid, which together form the buffer system in blood.

**Final Answer**: Sodium bicarbonate and carbonic acid (Option 4).

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