Maximum amount of oxygen is lost from the blood in

Options

A. arteries
B. capillaries of body
C. left atrium of the heart
D. Capillaries surrounding alveoli

Answer

To solve the question "Maximum amount of oxygen is lost from the blood in", we need to analyze the options provided and understand the physiological processes involved in oxygen transport and exchange in the human body.

### Step-by-Step Solution:

1. **Understanding Oxygen Transport**:
- Oxygen is transported in the blood primarily by binding to hemoglobin in red blood cells. The oxygenated blood is pumped from the heart to various parts of the body.

2. **Identifying the Sites of Oxygen Exchange**:
- Oxygen enters the bloodstream in the lungs via the alveoli, where it diffuses into the blood. However, this is not where oxygen is lost; it is where oxygen is gained.

3. **Analyzing the Options**:
- **Arteries**: These carry oxygenated blood from the heart to the tissues but do not facilitate the loss of oxygen.
- **Capillaries of the Body**: These are the smallest blood vessels where the actual exchange of gases occurs. Oxygen diffuses from the blood into the body tissues here, making this the primary site of oxygen loss.
- **Left Atrium of the Heart**: This chamber receives oxygenated blood from the lungs but does not participate in oxygen exchange with tissues.
- **Capillaries Surrounding Alveoli**: These are involved in the uptake of oxygen from the alveoli into the blood, not in the loss of oxygen.

4. **Conclusion**:
- The maximum amount of oxygen is lost from the blood in the **capillaries of the body** (Option B). This is where oxygen is delivered to the tissues that require it for cellular respiration.

### Final Answer:
The maximum amount of oxygen is lost from the blood in the **capillaries of the body**.

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