immune System Flashcards
pathogen
harmful disease causing organisms (bacteria plus viruses)
The immune system
defends body
first line of defense
skin mucus cilia stomach acid and saliva
Second line of defense (nonspecific)
White blood cells, phagocytes (engulfs bacteria), T cells (killer cells)
third line of defense
antibodies (very specific)
antigens constantly change
vaccine
weak, dead pathogen
body makes antibodies (response)
Active immunity:
: you make antibodies
passive immunity
given antibodies
epidermis
top layer of skin, sheds daily
saliva
contains chemicals that break down bacteria
White blood cells
attack if invaders enter body
normally circulate throughout blood but enters body tissue if detect invader
White blood cell phagocytes
eat foreign particles
interferon
A chemical that interferes with the ability for viruses to attack other cells
histamines
begins inflammatory response
capillaries dilated, temperature rises, pain receptors activate, white blood cells flock infected area
antibodies
proteins that latch onto damage clump and destroy pathogens
each antibody binds only to one specific binding site
