phagocytosis

• what are the two types of phagocyte

  macrophage

  neutrophil
• what is the main difference between the two phagocytes

  macrophages have a circular nucleus

  neutrophils have a lobed nucleus
• what happens in the first stage of phagocytosis

  macrophage binds to antigens on the pathogen and recognise it as foreign
• what happens in the second stage of phagocytosis

  pathogen is engulfed

  cell wall closes around pathogen

  phagosome formed
• what happens in the third stage of phagocytosis

  lysosomes fuse with phagosome

  phagolysosome formed

  hydrolytic enzymes digest pathogen
• what type of phagocyte has an extra step in this process

  macrophages
• what happens in the fourth stage of phagocytosis

  antigens of the pathogen bind to the MHC

  macrophage is now an antigen presenting cell
• what is the MHC

  major histocompatibility complex