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White blood cells play the role of scavenger. Most of them engulf and devour bacteria and other particles of foreign matter in the blood stream. Hence they prevent and fight infection and aid in wound repair. Pus is made up largely of dead white blood cells.
The names of various different kinds of white blood cells are long and complicated: for example, polymorphonuclear eosinophil. Because they devour bacteria, they are also called phagocytes. White blood cells are made in the bone marrow, the lymph nodes, and other places in the body.
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White blood cells are cells of the immune system involved in defending the body against …
only infectious disease
neither infectious disease nor foreign materials
only foreign materials
both infectious disease and foreign materials
