Shift to right of oxygen dissociation curve occurs at

Options

A. Lungs
B. Tissue with high temperature
C. Blood with high `pO_(2)`
D. Blood with high pH

Answer

### Step-by-Step Solution:

1. **Understanding the Oxygen Dissociation Curve**:
- The oxygen dissociation curve illustrates how hemoglobin binds to oxygen at various partial pressures of oxygen (pO2).
- It is typically sigmoid in shape, indicating that hemoglobin's affinity for oxygen changes with varying pO2 levels.

2. **Factors Affecting the Curve**:
- Several factors can influence the position of the oxygen dissociation curve:
- Temperature
- Partial pressure of carbon dioxide (pCO2)
- pH levels
- Partial pressure of oxygen (pO2)

3. **Right Shift of the Curve**:
- A rightward shift in the oxygen dissociation curve indicates a decreased affinity of hemoglobin for oxygen, meaning hemoglobin releases oxygen more readily.
- Conditions that cause a right shift include:
- **High temperature**: Increases metabolic activity and reduces hemoglobin's affinity for oxygen.
- **High pCO2**: Elevates carbon dioxide levels, which promotes the release of oxygen (Bohr effect).
- **Low pH**: Increased acidity (lower pH) also reduces hemoglobin's affinity for oxygen.

4. **Analyzing the Options**:
- A. **Lungs**: High pO2 in the lungs favors oxygen binding, causing a left shift.
- B. **Tissue with high temperature**: High temperature is a condition that promotes a right shift.
- C. **Blood with high pO2**: High pO2 favors oxygen binding, causing a left shift.
- D. **Blood with high pH**: High pH favors oxygen binding, causing a left shift.

5. **Conclusion**:
- The correct answer is **B. Tissue with high temperature**. This condition causes the oxygen dissociation curve to shift to the right, indicating a decreased affinity for oxygen.