Why is the volume of alveolar air less than that of the pulmonary ventilation ?

Explanation

To understand why the volume of alveolar air is less than that of pulmonary ventilation, we can break down the concepts involved:

### Step-by-Step Solution:

1. **Define Pulmonary Ventilation**:
- Pulmonary ventilation refers to the total volume of air that is moved in and out of the lungs per minute. It includes all the air that enters the respiratory system, regardless of whether it reaches the alveoli or not.
- In a normal adult, pulmonary ventilation is approximately 6.0 liters per minute.

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