Which of the following are referred to as mononuclear phagoytes?

• A. Lymphocytes and basophils.
• B. Mast cells and eosinophils.
• C. Basophils and eosinophils.
• D. Monocytes and macrophages.

Answer: (D)

Verified step by step guidance

1. Understand the term 'mononuclear phagocytes': These are immune cells that have a single round nucleus and are capable of phagocytosis, which is the process of engulfing and digesting cellular debris and pathogens.
2. Identify the types of cells that are considered mononuclear phagocytes: Monocytes and macrophages are the primary cells in this category.
3. Differentiate between mononuclear phagocytes and other immune cells: Lymphocytes, basophils, mast cells, and eosinophils have different functions and structures. For example, lymphocytes are involved in adaptive immunity, while basophils and eosinophils are involved in allergic responses and parasitic infections.
4. Recognize the role of monocytes: Monocytes circulate in the bloodstream and migrate into tissues where they differentiate into macrophages or dendritic cells.
5. Understand the function of macrophages: Once monocytes become macrophages, they act as scavengers, engulfing pathogens and dead cells, and play a crucial role in both innate and adaptive immunity.