The percentage of haemoglobin saturated with oxygen will increase if the

Options

A. arterial pH is decreased
B. temperature is increased
C. arterial `P_(2)` is incrased
D. `CO_(2)` concentration is increased

Answer

To determine the conditions under which the percentage of hemoglobin saturated with oxygen will increase, we need to analyze the factors that affect hemoglobin's binding affinity for oxygen. Here’s a step-by-step solution:

### Step 1: Understand Hemoglobin's Function
Hemoglobin is a protein in red blood cells that binds to oxygen in the lungs and releases it in the tissues. The saturation of hemoglobin with oxygen is influenced by various physiological factors.

**Hint:** Remember that hemoglobin's affinity for oxygen can change based on environmental conditions.

### Step 2: Analyze the Factors
1. **Arterial pH Decrease:** A decrease in pH (more acidic conditions) reduces hemoglobin's affinity for oxygen, leading to less saturation.

**Hint:** Consider how acidity affects protein structure and function.

2. **Increased Temperature:** An increase in temperature also decreases hemoglobin's affinity for oxygen, resulting in lower saturation levels.

**Hint:** Think about how heat can affect molecular interactions.

3. **Increased Arterial Pressure:** An increase in arterial pressure enhances the binding of oxygen to hemoglobin, increasing saturation levels.

**Hint:** Consider how pressure can influence gas solubility and binding.

4. **Increased Carbon Dioxide Concentration:** Higher levels of carbon dioxide decrease hemoglobin's affinity for oxygen, leading to lower saturation.

**Hint:** Reflect on the relationship between carbon dioxide and oxygen transport in the body.

### Step 3: Identify the Correct Option
From the analysis:
- Decreased pH, increased temperature, and increased carbon dioxide concentration all lead to decreased saturation of hemoglobin with oxygen.
- Increased arterial pressure, however, leads to an increase in hemoglobin's binding affinity for oxygen, thereby increasing saturation.

### Conclusion
The percentage of hemoglobin saturated with oxygen will increase if the **arterial pressure is increased**.

**Final Answer:** Increased arterial pressure.

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