A macrophage is a type of leukocyte that surrounds and kills invading cells. This cell type also removes dead cells as well as stimulates the action of other immune cells.
Leukocytes are the white blood cells present inside the body. These are synthesized in the bone marrow of the bones. The cells may be present in blood as well as the lymph fluid. The most important function of leukocytes is to help in maintaining and increasing the immunity of the body by fighting the foreign invaders.
Immunity is the ability of the body to protect itself by fighting with the foreign invaders like bacteria, viruses etc. More healthy and disease-free an organism is, more is his immunity.
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