Which of the following condition is not reponsible
for shifting the curve towards left in oxyhaemoglobin dissociation curve ?

Options

A. High `pO_(2)`
B. Low `pCO_(2)`
C. Low temperature
D. High `H^(+)` ion concentration

Answer

To determine which condition is not responsible for shifting the oxyhemoglobin dissociation curve towards the left, we need to understand the factors that influence this curve. The oxyhemoglobin dissociation curve illustrates how hemoglobin binds with oxygen at various partial pressures of oxygen (pO2).

### Step-by-Step Solution:

1. **Understanding the Oxyhemoglobin Dissociation Curve**:
- The curve shows the relationship between the partial pressure of oxygen (pO2) and the saturation of hemoglobin with oxygen.
- A leftward shift in the curve indicates an increased affinity of hemoglobin for oxygen, meaning hemoglobin binds more readily to oxygen.

2. **Factors that Cause Leftward Shift**:
- **High pO2**: When the concentration of oxygen is high, hemoglobin binds more oxygen, shifting the curve to the left.
- **Low pCO2**: A lower concentration of carbon dioxide (CO2) in the blood leads to a higher pH (less acidic), which also favors the binding of oxygen to hemoglobin, shifting the curve left.
- **Low Temperature**: A decrease in temperature increases hemoglobin's affinity for oxygen, resulting in a leftward shift.
- **Low H+ Concentration**: A lower concentration of hydrogen ions (H+) corresponds to a higher pH, which also promotes oxygen binding, shifting the curve left.

3. **Identifying the Incorrect Option**:
- The question asks for the condition that does **not** cause a leftward shift.
- **High H+ Concentration**: This condition would lead to a lower pH (more acidic), which decreases hemoglobin's affinity for oxygen and shifts the curve to the right, not left.

4. **Conclusion**:
- The correct answer is **high H+ concentration**, as it does not favor a leftward shift in the oxyhemoglobin dissociation curve.