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.