Which of the following factors favour the formation of oxyahemoglobin in lungs ?

Options

A. `pO_(2) darr pCO_(2) uarr , "Temperaure" uarr , H^(+) "concentration " uarr ^(2)`
B. `pO_(2) uarr pCO_(2) uarr, " Temperaure " darr , H^(+) " Concentration " uarr^(2)`
C. `pO_(2) darr pCO_(3) pCO_(2) uarr, "Temperaure" darr, H^(+) "concentration" darr ^(2)`
D. `pO_(2) uarr pCO_(2) darr, " Temperaure " darr, H^(+) "concentration " darr^(2)`

Answer

To determine which factors favor the formation of oxyhemoglobin in the lungs, we need to analyze the four options provided based on the physiological principles governing hemoglobin's interaction with oxygen and carbon dioxide.

### Step-by-Step Solution:

1. **Understanding Oxyhemoglobin Formation**:
- Oxyhemoglobin is formed when hemoglobin binds with oxygen. The binding is influenced by several factors, including the partial pressures of oxygen (pO2) and carbon dioxide (pCO2), temperature, and pH.

2. **Analyzing the Factors**:
- **Partial Pressure of Oxygen (pO2)**:
- High pO2 favors the formation of oxyhemoglobin. When oxygen levels are high, hemoglobin is more likely to bind with oxygen.
- **Partial Pressure of Carbon Dioxide (pCO2)**:
- High pCO2 does not favor the formation of oxyhemoglobin. Increased carbon dioxide levels can lead to a decrease in hemoglobin's affinity for oxygen.
- **Temperature**:
- Higher temperatures reduce the affinity of hemoglobin for oxygen, thus not favoring oxyhemoglobin formation. Lower temperatures favor the binding of oxygen to hemoglobin.
- **pH (H+ Ion Concentration)**:
- A higher pH (lower H+ concentration) favors the formation of oxyhemoglobin. Conversely, a lower pH (higher H+ concentration) reduces hemoglobin's affinity for oxygen.

3. **Evaluating the Options**:
- **Option A**: pO2 is less - Not favorable for oxyhemoglobin formation.
- **Option B**: pO2 is more, pCO2 is more - pO2 is favorable, but high pCO2 is not favorable.
- **Option C**: pO2 is less - Not favorable.
- **Option D**: pO2 is more, pCO2 is less, temperature is less, and pH is more - All these conditions are favorable for the formation of oxyhemoglobin.

4. **Conclusion**:
- The correct answer is **Option D**, as it includes all factors that favor the formation of oxyhemoglobin in the lungs.