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Biology> Immunity> Phagocytosis

Phagocytosis is carried out by both neutrophils and macrophages.

Cells under attack produce histamine.

Pathogens release chemicals.

These both attract phagocytes (chemotaxis).

Pathogens may be covered in marker antibodies (from B lymphocytes).

This stimulates phagocytes to attack as they have receptor proteins which recognise antibody molecules and attach to them.

Phagocyte membrane engulfs pathogen and traps it in a vacuole (endocytosis).

Digestive enzymes within lysosomes fuse with phagocytic vacuole and the pathogen is destroyed.

Undigested remains are removed by exocytosis.