diseases and imunity Flashcards
pathogen
a microorganisms that causes diseases
host
organism that the pathogen lives and reproduces within
infection
the entry of a pathogen in the body
transmission
movement of a pathogen from one host to another
transmissible disease
disease caused by pathogens that can be passed from one host to another
once inside our body, pathogens damage our cells by:
using up our rescources
producing waste products called toxins which cause simptons
som toxins are highly toxic
direct contract
direct contact from an infected person to another
indirect transmission
breathing in droplets containing pathogens
thouching a surface that someone with the pathogen has touched
eating food that contains pathogens
contact w/ animals carrying pathogens
body defenses against pathogens
skin- prevents pathogens from entering the body. if skin is broken = blood clot
HCL in stomach- kills bacteria in our food
hairs in nose- filter out particles from the air, which could have pathogens
mucus- in airways traps bacteria. then swallowed instead of to the lungs
smell + taste- if it smells or taste bad then we don’t want to eat it
then white blood cells
clean water
basic human need
before coming to our houses its filtered
dirty water contains pathogens
food hygiene
most food poisoning is caused by bacteria
keed animals away
keep food at low or high temps
keep raw meat away
personal hygiene
skin makes oil to keep is supple and waterproof
if this builds up it can callect dirt and microbes
sweat dirt are breeding grounds for bacteria
waste disposal
humans produce alot of waste
collecting waste to avoid pollution
landfill sites
some trash is rotted by decomposers
bacteria produce methan gas which is higly flammable
should be let our through pies or used for feul
filled sites are covered with soil and grass
sewage
liquid waste
mostly water
raw sewage must be treated before going into rivers or seas
cholera
spread through water/ food that has been contaminated by faeces of infected people
lives and spreads in the small intestine
how cholera spreads in the small intestine
cholera ingested
attack walls of alimentary canal
release toxin
toxin causes Cl- ions to be released
this causes water to move into the lumen by osmosis
now alot of water in canal
blood contain too little Cl- and H2O
could die from dehydration and loss of Cl
antibodies
molecules secreted by white blood cells, which bind to pathogens and destroy them
proteins that have a complimentary shape to the antigens
antigen
a chemical that is recognized by the body as being foreign and stimulates production of antibodies
usually on outside of pathogen
immune response
the reaction of the body to the presence of a pathogen
when a pathogens enters the body…
it is detected by the lymphocyte that then divides into and produces antibodies
memory cells
long-lived cells produced by the division of lymphocytes that have contacted an antigen. they respond quickly to future contact with that antigen. and the imune response, memory cells stay in the blood for a long time
vaccination
a harmless preperation of dead pathogens that is injected into the bodyto start the immune repsonse
vaccines can be made using
dead cells from the disease
pieces of cells from the disease
cells from a similar disease
first dose of a vaccination
partial protection = stimulates production of some memory cells
second dose
“booster” = stimulates the production of more memory cells
active immunity
if thier body made its own antibodies and memory cells that protects against a disease
active immunity is developed through
having the disease and recovering
being vaccinated
can last long
passive immunity
if they have been given ready made antibodies that have been made by another organism
passive immunity is developed through
breastfeeding a baby
injection
last short
