Lungs have a large number of alveoli for

Options

A. Having spongy texture and proper shape
B. More surface are for diffusion of gases
C. More space for increasing volume of inspired air
D. More nerve supply.

Answer

**Step-by-Step Solution:**

1. **Understanding the Role of Lungs:**
- The lungs are essential organs in the respiratory system responsible for gas exchange, specifically the intake of oxygen and the expulsion of carbon dioxide.

2. **Identifying Alveoli:**
- Alveoli are tiny air sacs located within the lungs. They are the primary sites where gas exchange occurs.

3. **Function of Alveoli:**
- The main function of alveoli is to facilitate the exchange of gases (oxygen and carbon dioxide) between the air in the lungs and the blood in the capillaries surrounding them.

4. **Importance of Surface Area:**
- The lungs contain a large number of alveoli, which significantly increases the surface area available for gas exchange. A larger surface area allows for more efficient diffusion of gases.

5. **Diffusion Process:**
- Gas exchange occurs through diffusion, where oxygen moves from areas of higher concentration (in the alveoli) to lower concentration (in the blood), and carbon dioxide moves in the opposite direction.

6. **Structural Adaptations of Alveoli:**
- Alveoli have thin walls, which facilitate rapid diffusion. Their irregular shape also contributes to maximizing surface area.

7. **Conclusion:**
- The large number of alveoli in the lungs is crucial for providing an extensive surface area that enhances the efficiency of gas exchange, allowing the body to meet its oxygen demands and remove carbon dioxide effectively.

**Final Answer:**
Lungs have a large number of alveoli to provide a greater surface area for the diffusion of gases, which enhances the efficiency of gas exchange.

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