How are the lungs designed in human beings to maximise the area for exchange of gases?

Explanation

**Step-by-Step Solution:**

1. **Understanding the Structure of Lungs**: The lungs are vital organs in the human body responsible for gas exchange. They are designed to maximize the surface area available for this exchange.

2. **Role of Alveoli**: The primary units of gas exchange in the lungs are called alveoli. These are tiny, balloon-like structures that are crucial for the respiratory process.

3. **Quantity of Alveoli**: In a healthy human lung, there are approximately 300 to 350 million alveoli. This high number significantly increases the surface area available for gas exchange.

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