An increases in the `P_(50)` of an oxyhaemoglobin curve would result from a decrease in

Options

A. pH
B. carbondioxide
C. metabolism
D. temperature

Answer

To solve the question regarding the increase in P50 of an oxyhemoglobin curve resulting from a decrease in a specific factor, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Oxyhemoglobin Dissociation Curve**:
- The oxyhemoglobin dissociation curve shows the relationship between the partial pressure of oxygen (P_O2) and the saturation of hemoglobin with oxygen. It is typically a sigmoid (S-shaped) curve.

2. **Define P50**:
- P50 is the partial pressure of oxygen at which hemoglobin is 50% saturated with oxygen. A higher P50 value indicates that a higher partial pressure of oxygen is required for hemoglobin to achieve 50% saturation.

3. **Identify Factors Affecting the Curve**:
- The oxyhemoglobin curve is influenced by several factors, including pH, carbon dioxide concentration, and temperature. Changes in these factors can cause the curve to shift to the right or left.

4. **Analyze the Effect of pH**:
- A decrease in pH (which indicates an increase in acidity) causes the oxyhemoglobin curve to shift to the right. This means that at any given partial pressure of oxygen, hemoglobin will have a lower saturation percentage.

5. **Relate pH to P50**:
- When the curve shifts to the right due to a decrease in pH, the P50 value increases. This is because hemoglobin requires a higher partial pressure of oxygen to achieve 50% saturation.

6. **Conclusion**:
- Therefore, an increase in the P50 of the oxyhemoglobin curve results from a decrease in pH.

### Final Answer:
An increase in the P50 of an oxyhemoglobin curve would result from a decrease in pH.

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