- Pathogen enters the body
- White blood cells are alerted to the pathogen entering the body
- Phagocytes engulf and digest the pathogen
- Lymphocytes secrete antibodies and break the bacteria down
- White blood cells – specialized cells which stop pathogens
- Pathogens – have antigens (proteins) on their cell surfaces which make them harmful
- Lymphocytes -make antibodies to counteract the antigens, specific to the pathogen. The antibodies make the pathogen stick together so that the phagocytes engulf them easier, they also neutralise the toxins produced by the bacteria. When a lymphocyte meets it’s pathogen, it divides into two – the first half as memory cells so it can build the immune system, and the other to secrete antibodies.
- Phagocytes – detects the presence of a pathogen because of the chemicals they give off, engulfs the pathogen and destroys the cell with digestive enzymes.