All of the following factors are favourable for the formation of oxyhaemoglobin, except

Options

A. High pO2
B. Less H+ ions concentration
C. Low pH
D. Low Temperature

Answer

To solve the question regarding the factors that favor the formation of oxyhemoglobin, we need to analyze each option provided. The goal is to identify which factor does not favor the formation of oxyhemoglobin.

### Step-by-Step Solution:

1. **Understanding Oxyhemoglobin Formation**:
Oxyhemoglobin is formed when oxygen binds to hemoglobin in red blood cells. Several factors influence this binding process.

2. **Analyzing Each Option**:
- **Option 1: High Partial Pressure of Oxygen**:
- A high partial pressure of oxygen (pO2) facilitates the binding of oxygen to hemoglobin. Therefore, this factor is favorable for the formation of oxyhemoglobin.

- **Option 2: Lesser Hydrogen Ion Concentration**:
- A lower concentration of hydrogen ions (higher pH) is favorable for the formation of oxyhemoglobin. When hydrogen ion concentration is lower, it promotes the binding of oxygen to hemoglobin. Thus, this factor is also favorable.

- **Option 3: Low pH**:
- A low pH indicates a higher concentration of hydrogen ions, which leads to the dissociation of oxyhemoglobin. This means that hemoglobin releases oxygen instead of binding to it. Therefore, low pH is not favorable for the formation of oxyhemoglobin.

- **Option 4: Low Temperature**:
- Low temperatures favor the formation of oxyhemoglobin because they promote the binding of oxygen to hemoglobin. High temperatures would lead to the dissociation of oxygen from hemoglobin. Thus, low temperature is favorable for oxyhemoglobin formation.

3. **Conclusion**:
After analyzing all the options, we find that the only factor that does not favor the formation of oxyhemoglobin is **Option 3: Low pH**.

### Final Answer:
The correct answer is **Option 3: Low pH**.

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