Oxyhaemoglobin acts as

Options

A. Alkali
B. Acid
C. Neutral
D. Buffer

Answer

**Step-by-Step Solution:**

1. **Understanding Oxyhemoglobin:**
- Oxyhemoglobin is represented as HbO2, which is formed when hemoglobin (Hb) binds with oxygen (O2). It is primarily found in red blood cells (RBCs), also known as erythrocytes.

2. **Properties of Oxyhemoglobin:**
- Oxyhemoglobin is known to be acidic in nature. This means it tends to release protons (H+) in solution, contributing to the acidity.

3. **Oxygen-Hemoglobin Dissociation Curve:**
- The oxygen-hemoglobin dissociation curve is a sigmoid-shaped graph that illustrates how hemoglobin's oxygen binding affinity changes with varying levels of oxygen and carbon dioxide, as well as pH levels.

4. **Effect of pH and CO2:**
- The dissociation of oxyhemoglobin is influenced by pH and the concentration of carbon dioxide (CO2). An increase in CO2 concentration or a decrease in pH (more acidic conditions) promotes the release of oxygen from hemoglobin.

5. **Conclusion:**
- Based on the properties and behavior of oxyhemoglobin, it can be concluded that oxyhemoglobin acts as an acid. Therefore, the correct answer to the question is that oxyhemoglobin acts as an acid.

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