Which of the following factors are favorable for the formation of oxyhemoglobin ?
(a) High `p_(O_(2))`, low `p_(CO_(2))`
(b) Lesser `H^(+)` concentration, lower temperature
( c) Low `p_(O_(2))`, high `CO_(2)`
(d) High `H^(+)` , higher temperature

Options

A. (A) only
B. (A) and (B)
C. (B) and (C)
D. (C) and (D)

Answer

To determine which factors are favorable for the formation of oxyhemoglobin, we need to analyze each of the given options based on the principles of gas exchange and hemoglobin's behavior.

### Step-by-Step Solution:

1. **Understanding Oxyhemoglobin Formation**:
- Oxyhemoglobin is formed when oxygen binds to hemoglobin in red blood cells. The binding is influenced by several factors, including the partial pressures of oxygen (pO2) and carbon dioxide (pCO2), temperature, and the concentration of hydrogen ions (H+).

2. **Analyzing Statement (a)**: High pO2, low pCO2
- High partial pressure of oxygen (pO2) promotes the binding of oxygen to hemoglobin, making this condition favorable for oxyhemoglobin formation.
- Low partial pressure of carbon dioxide (pCO2) reduces competition for binding sites on hemoglobin, further favoring the formation of oxyhemoglobin.
- **Conclusion**: This statement is correct.

3. **Analyzing Statement (b)**: Lesser H+ concentration, lower temperature
- A lower concentration of hydrogen ions (H+) indicates a more alkaline environment, which favors the binding of oxygen to hemoglobin.
- Lower temperature also favors oxyhemoglobin formation, as increased temperature can lead to the dissociation of oxygen from hemoglobin.
- **Conclusion**: This statement is correct.

4. **Analyzing Statement (c)**: Low pO2, high pCO2
- Low partial pressure of oxygen (pO2) means there is less oxygen available to bind with hemoglobin, making it unfavorable for oxyhemoglobin formation.
- High partial pressure of carbon dioxide (pCO2) promotes the formation of carbaminohemoglobin instead of oxyhemoglobin.
- **Conclusion**: This statement is incorrect.

5. **Analyzing Statement (d)**: High H+, higher temperature
- High concentration of hydrogen ions (H+) indicates an acidic environment, which reduces the affinity of hemoglobin for oxygen, thus favoring dissociation rather than binding.
- Higher temperature also leads to the dissociation of oxygen from hemoglobin.
- **Conclusion**: This statement is incorrect.

### Final Answer:
The factors that are favorable for the formation of oxyhemoglobin are:
- (a) High pO2, low pCO2
- (b) Lesser H+ concentration, lower temperature

Thus, the correct options are (a) and (b).

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