Active and Passive Immunity Flashcards
immunity
you have antibodies in your blood against a particular pathogen that stops you from getting sick when the pathogen enters your body
do antibodies last forever
they degrade as they are proteins
what are the four ways of gainingg immunity
active and passive immunity, artificial and natural immunity
natural immunity
immunity acquired unintentionally by interaction with other biological entities
artificial immunity
immunity acquired intentionally usually by the means of artificial technology
active immunity
when a persons own immune system produces the specific antibodies to a particular antigen
components of active immunity
memory cells are made so immunity is long lived, can be natural/artificial
passive immunity
when antibodies are recieved from an extrenal source, antibodies are not being made by the individual who is recieving them
componenets of passive immunity
no memory cells will be produced because the immune system has not been stimulated against the antigen, therrefore immunity is short lived, can be natural/artificial
natural active immunity
individual naturally encounters a pathogen that enters the body and an immune response is triggered, is a priimary response, memory cells are produced and symptoms are usually present
artificial active immunity
the individual is injected with a vaccine and the immuen response is triggered, is a primary response, memory cells are produced, symptoms usually arent present as the pathogen has been weakened/modified
natural passive immunity
recieving antibodies across the placenta from mother to unborn baby or through breast milk from mother to baby
natural passive immunity components
no memory cells produced so immunity maylast a couple of months
artificial passive immunity
injecting antibodies that have been made from another organism, e.g anti-venom or tetanus injection
inactivated vaccines
contain whole bacteria/viruses that have been altered/killed so they can’t reproduce
live-attenuated vaccine
contain whole bacteria/viruses that have been weakened through genetic modification/other means
what is the principle that all vaccines follow
presenting b lymphocytes with antigens that will stimulate them to undergo clonal expansion, most vaccines contain one or more antigens from the pathogen rather than the whole pathogen
what are the two immune responses of active immunity
primary immune response and secondary immune response
primary immune reponse
first exposure to the antigen, moderate amount of antibodies will be produced at a slow pace, less antibodies produced and they will diminish quickly
secondary immune response
second exposure to the apthigen, the memory cells recognise the antigens resulting in a quicker and larger production of antibodies and memory cells
why does the second exposure cause so manyy more antibodies to be produced and at a faster rate
as many b cells are undergoing clonal expansion and differentiation not just 1
innoculate
deliberatley introduce forgein antigens into the body
why do we ttake booster shots
memory b and t cells die after a long time, this leads to an individual becoming susceptable to disease again. when a booster vaccine is administered any remaining memory cells are stimulated, restoring immunity
herd immunity
achieved when majority of people ina population/community are immune to a particular pathogen, helping prevent tthe spread of the pathogen to those who havent been vaccinated or already infected
how does herd immunity prevent people who cannot be vaccinated from being infected
if a large proportion of individuals are vaccinated than the disease cannot easilyy reproduce and spread throughout the population, hence these people are lless likely to come into contact with an individual harbouring the pathogen