AP BIOLOGY

Detailed explanation-1: -Some types of white blood cells, called phagocytes (pronounced: FAH-guh-sytes), chew up invading organisms. Others, called lymphocytes (pronounced: LIM-fuh-sytes), help the body remember the invaders and destroy them. One type of phagocyte is the neutrophil (pronounced: NOO-truh-fil), which fights bacteria.

Detailed explanation-2: -However, only a specialized group of cells called professional phagocytes (1) accomplish phagocytosis with high efficiency. Macrophages, neutrophils, monocytes, dendritic cells, and osteoclasts are among these dedicated cells.

Detailed explanation-3: -Killer T-cells directly kill cells that have already been infected by a foreign invader.

Detailed explanation-4: -Macrophages have a long life span, reside in the tissues, and are the first phagocyte that invading organisms encounter upon entering the body. Neutrophils and macrophages work in concert with each other and are crucial to the host’s defense against all intracellular and extracellular pathogens [4].

Detailed explanation-5: -Professional phagocytes play a central role in innate immunity by eliminating pathogenic bacteria, fungi and malignant cells, and contribute to adaptive immunity by presenting antigens to lymphocytes.