In lungs macrophages help in removal of

Options

A. Microorganisms
B. Dust and fibres
C. Cell debris
D. All the above.

Answer

**Step-by-Step Solution:**

1. **Understanding Macrophages**: Macrophages are a type of immune cell that play a crucial role in the body's defense mechanisms. In the lungs, they are specifically referred to as alveolar macrophages or dust cells.

2. **Function of Alveolar Macrophages**: The primary function of alveolar macrophages is to identify and eliminate harmful substances that enter the lungs. These include pathogens (like bacteria and viruses), dust particles, and cellular debris.

3. **Inhaled Air Composition**: When we breathe in, the air contains not only oxygen but also various particles, including microorganisms, dust, and fibers. These can pose a risk to our respiratory health.

4. **Role in Clearance**: Alveolar macrophages help to clear the respiratory pathways by engulfing and digesting these harmful particles. This process is essential for maintaining lung health and preventing infections.

5. **Conclusion**: Given that alveolar macrophages are involved in the removal of all the mentioned substances—microorganisms, dust and fibers, and cell debris—the correct answer to the question is "all the above".

**Final Answer**: In lungs, macrophages help in the removal of microorganisms, dust and fibers, cell debris; that is, all the above.

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