Which type of leukocyte primarily functions as an antigen-presenting cell?

• A. Eosinophil
• B. Dendritic cell
• C. Basophil
• D. Neutrophil

Answer: (B)

Verified step by step guidance

1. Understand the role of leukocytes (white blood cells) in the immune system. Leukocytes are responsible for defending the body against pathogens and include various types with specialized functions.
2. Learn the concept of antigen-presenting cells (APCs). APCs are immune cells that capture antigens, process them, and present them on their surface to T cells, initiating an adaptive immune response.
3. Identify the leukocyte types listed in the problem: Eosinophils, Basophils, Neutrophils, and Dendritic cells. Each has distinct functions in the immune system.
4. Recall that dendritic cells are the primary antigen-presenting cells. They are highly efficient at processing antigens and activating T cells, making them central to adaptive immunity.
5. Review the functions of the other leukocytes: Eosinophils combat parasitic infections, Basophils release histamine during allergic reactions, and Neutrophils are phagocytes that target bacteria and fungi. None of these primarily function as antigen-presenting cells.