antigens and phagocytosis

• what is an antigen?

  a protein found on the outside of cells that triggers an immune response by lymphocytosis
• what is an antibody?

  a protein produced by lymphocytes in response to the presence of the appropriate antigen
• what is a lymphocytes?

  types of white blood cell responsible for the immune response, they become activated in the presence of antigens
• what is a phagocyte?

  a type of white blood cell which carried out a non-specific immune response and ingests and breaks down pathogens by phagocytosis
• what is phagocytosis?

  a cellular process of engulfing solid particles using the cell membrane carried out by phagocytosis
• The process of phagocytosis:

  • pathogen recognised as having foreign antigens
  • pathogen attaches to the phagocyte by surface receptors
  • pathogen is engulfed by the phagocyte by endocytosis forming a phagosome
  • lysosomes fuse to phagosomes to form a phagolysosome and release digestive enzymes into phagosome to digest pathogen
  • harmless products are excreted by exocytosis by phagocyte

  
• phagocytes are non specific and act against any foreign cells or materials
• lymphocytes are specific and are responsible for immunity
• phagocytes require lots of ATP, because of endocytosis
• lysosome is a vesicle containing lysozyme (enzymes that split cells)
• your immune system works slightly better at increased temperatures and pathogens work slightly worse, that's why you get fevers