What role of macrophages play. in providing immunity to humans ?

Explanation

**Step-by-Step Text Solution:**

1. **Definition of Macrophages**: Macrophages are a type of white blood cell (WBC) that play a crucial role in the immune system. They are classified as phagocytes, which are cells that can engulf and digest cellular debris and pathogens.

2. **Detection of Pathogens**: The first step in the immune response is the detection of pathogens (harmful microorganisms such as bacteria and viruses) by macrophages. They have receptors that recognize specific components of these pathogens.

3. **Engulfment Process**: Once a pathogen is detected, macrophages engulf it through a process called phagocytosis. This involves the macrophage extending its membrane around the pathogen, enclosing it in a vesicle.

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