Alveoli provide the surface area for exchange of ________.

Options

A. food
B. enzymes
C. gases
D. hormones

Answer

**Step-by-Step Solution:**

1. **Understanding Alveoli**: Alveoli are tiny air sacs located in the lungs where gas exchange occurs. They are crucial for the respiratory system.

2. **Identifying the Function**: The primary function of alveoli is to facilitate the exchange of gases between the air we breathe and the blood.

3. **Types of Gases Involved**: The gases exchanged in the alveoli are oxygen (O2) and carbon dioxide (CO2). Oxygen is absorbed into the blood, while carbon dioxide is released from the blood into the alveoli to be exhaled.

4. **Mechanism of Exchange**: The exchange of gases occurs through a process called diffusion, where gases move from an area of higher concentration to an area of lower concentration.

5. **Conclusion**: Therefore, the alveoli provide the surface area for the exchange of gases, specifically oxygen and carbon dioxide.

**Final Answer**: Alveoli provide the surface area for the exchange of gases.

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