MICROANATOMY

Detailed explanation-1: -Out of the WBCs, there are only three that are phagocytic namely neutrophils, monocytes, and eosinophils. Eosinophil cells fight allergic and parasitic infections. Out of these three, neutrophils and monocytes are the most active phagocytic cells.

Detailed explanation-2: –Neutrophils are phagocytes which ingest microorganisms or particles by the process called as antibody opsonization.-Thus, phagocytosis by neutrophils and monocytes is a key process in innate immune response. The most active phagocytes are Neutrophils and Monocytes.

Detailed explanation-3: -Answer and Explanation: The correct answer is D. The most active phagocytic cells found in circulating blood are neutrophils and monocytes. Neutrophils are the most abundant type of white blood cell in the blood.

Detailed explanation-4: -Monocytes can phagocytose and present antigens, secrete chemokines, and proliferate in response to infection and injury. Once recruited to tissues, monocytes are capable of differentiating into macrophages and dendritic cells.

Detailed explanation-5: -Polymorphonuclear neutrophils (PMNs) and monocyte/macrophages (MMs) are professional phagocytic cells that are able to phagocytose and destroy infectious agents. Therefore, they are key anti-infectious actors in host defense but can mediate tissue damages.