Final answer:
Mononuclear phagocytes are primarily monocytes and macrophages, which are involved in the phagocytosis process, different from other leukocytes that participate in the inflammatory response.
Step-by-step explanation:
The mononuclear phagocytes system comprises of various immune cells that are primarily involved in the process of phagocytosis, where they engulf and digest cellular debris, foreign substances, microbes, and cancer cells. Amongst the types of leukocytes, which are white blood cells, monocytes and their derivatives, macrophages, are the primary cells in the mononuclear phagocyte system. Monocytes circulate in the blood and upon migrating into tissues, they differentiate into macrophages which are highly efficient phagocytic cells. They are not to be confused with mast cells, basophils, or granulocytes such as neutrophils and eosinophils which have other roles typically associated with the inflammatory response and in the case of neutrophils, acute phagocytosis.