the immune system Flashcards
what happens when pathogens overcome all physical and chemical barriers?
immune system becomes active and attack pathogens
what are the molecules called on the outer surfaces of cells and virus particles?
antigens
what does the immune system antigens for?
to identify if something inside the body is a cell of the body or has come from outside (foreign)
give an example of white blood cells
lymphocytes
what molecules do lymphocytes have on their surfaces?
antibodies
what do antibodies do?
match the shape of antigens on the pathogen
stops pathogen from working
what happens to lymphocytes after they have matched the pathogens antigens?
it becomes activated and divides rapidly to produce identical lymphocytes with the same antibodies
these then spread to other parts of immune system destroying other matched pathogens
when all the pathogens have been killed , some lymphocytes with antibodies that match that pathogen’s antigens remain in the blood. what are they called?
memory lymphocytes
how will your body react if that pathogen attacks again?
memory lymphocytes mean that a much faster secondary response will happen that will stop you getting ill
YOU ARE IMMUNE TO THAT PARTICULAR PATHOGEN
name an artificial way to become immune to a pathogen
a vaccine
what does a vaccine contain?
weakened or inactive pathogens
bits of pathogen that include the antigens
how do you administrate a vaccine?
by injection or mouth
