Body tissues obtain oxygen from oxyhaemoglobin because of its dissociation caused by :

Options

A. low oxygen concentration
B. low concentration
C. high concentration
D. low and high concentration

Explanation

To answer the question, "Body tissues obtain oxygen from oxyhaemoglobin because of its dissociation caused by:", we need to understand the factors that influence the dissociation of oxyhaemoglobin in the body tissues.

### Step-by-Step Solution:

1. **Understanding Oxyhaemoglobin**:
- Oxyhaemoglobin is formed when hemoglobin in the blood binds with oxygen in the lungs. This complex is crucial for transporting oxygen from the lungs to the body tissues.

2. **Dissociation of Oxyhaemoglobin**:
- For body tissues to obtain oxygen, oxyhaemoglobin must dissociate, releasing oxygen. This process is influenced by various factors present in the tissues.

3. **Factors Influencing Dissociation**:
- The dissociation of oxyhaemoglobin is influenced by:
- **Partial Pressure of Oxygen (pO2)**: Low levels of oxygen in the tissues promote dissociation.
- **Partial Pressure of Carbon Dioxide (pCO2)**: High levels of carbon dioxide in the tissues promote dissociation.
- **Temperature**: Increased temperature in the tissues promotes dissociation.
- **pH Level (H+ Concentration)**: A higher concentration of H+ ions (lower pH) promotes dissociation.

4. **Conclusion**:
- Therefore, the correct answer to the question is that the dissociation of oxyhaemoglobin is caused by low oxygen concentration, high carbon dioxide concentration, increased temperature, and increased H+ ion concentration in the body tissues.

5. **Final Answer**:
- The body tissues obtain oxygen from oxyhaemoglobin because of its dissociation caused by low oxygen concentration, high carbon dioxide concentration, increased temperature, and increased H+ ion concentration.