ATI Pathophysiology Practice Exam

Which type of cells is primarily responsible for the destruction of old cells and invasive microorganisms?

1. Neutrophils

2. Eosinophils

3. Macrophages

4. Basophils

The correct answer is: Macrophages

Macrophages play a crucial role in the immune system by being the primary cells responsible for the destruction of old cells and invasive microorganisms. These large phagocytic cells originate from monocytes, a type of white blood cell, and migrate from the bloodstream to various tissues throughout the body. Once located in tissues, macrophages are able to engulf and digest cellular debris, foreign particles, and pathogens through a process known as phagocytosis. In addition to clearing away dead cells and microorganisms, macrophages also play a vital role in activating other immune cells and orchestrating the immune response. They release various cytokines that help to recruit other immune cells to sites of infection or injury, enhancing the body's ability to respond effectively to threats. This function of macrophages contrasts with other types of cells involved in the immune response. Neutrophils, while also important phagocytes, primarily respond to acute infections but are generally less effective at clearing dead cells compared to macrophages. Eosinophils are mainly involved in combating parasitic infections and allergic responses, while basophils play a role in inflammatory reactions but do not have a direct role in phagocytosis like macrophages. Thus, the primary responsibility for the destruction of old cells and