In the tissues, high concentrations of carbon dioxide

Options

A. increases the affinity of haemoglobin to both oxygen and hydrogen
B. increases the affinity of haemoglobin to oxygen but decreases its affinity to hydrogen
C. decrease the affnitiy to haemoglobin to oxygen but increases its affinity to hydrogen
D. decrease the affinity of haemoglobin to both oxygen and hydrogen.

Explanation

To solve the question regarding the effect of high concentrations of carbon dioxide in tissues on hemoglobin's affinity for oxygen and hydrogen, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Role of Carbon Dioxide**: In tissues, when metabolic activity increases, carbon dioxide (CO2) levels also rise. This is because cells produce CO2 as a byproduct of respiration.

2. **Effect on Blood pH**: The increase in CO2 concentration leads to a decrease in the pH of the blood. This is due to the formation of carbonic acid when CO2 dissolves in blood, which dissociates into bicarbonate and hydrogen ions.

3. **Boehr Effect**: The decrease in pH (increase in hydrogen ions) is known as the Bohr effect. This effect describes how increased CO2 and decreased pH reduce hemoglobin's affinity for oxygen. This means that hemoglobin will release more oxygen in tissues where CO2 levels are high.

4. **Affinity for Hydrogen Ions**: While hemoglobin's affinity for oxygen decreases in the presence of high CO2, its affinity for hydrogen ions increases. Deoxygenated hemoglobin (deoxyhemoglobin) binds to hydrogen ions more effectively than oxygenated hemoglobin (oxyhemoglobin).

5. **Conclusion**: Therefore, in high concentrations of carbon dioxide, hemoglobin decreases its affinity for oxygen but increases its affinity for hydrogen ions.

### Final Answer:
The correct option is: **Decreases the affinity of hemoglobin to oxygen but increases its affinity to hydrogen** (Option C).

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