B6 - preventing and treating disease fact test Flashcards
what is a vaccination
a small quantity of dead or inactive form of pathogen
what is herd immunity
when enough people are immune to a certain pathogen to reduce the spread of pathogen
what effect does a vaccination have
- vaccination is injected into the body to stimulate the white blood cells to produce specific antibodies
- this means that if the same pathogen re-enters the body, the white blood cells respond quickly to produce the correct antibodies, preventing the person from becoming ill
what happens after secondary exposure
- increase in antibodies begins sooner
- increase in antibodies is faster
- more antibodies are produced
- antibodies re longer lasting
what are antibiotics
medicines that help cure bacterial disease by killing infectious bacteria inside the body
note that specific bacteria should be treated by specific antibodies
why can’t antibiotics treat viral diseases
viruses replicate inside of cells and antibiotics can’t get to them without damaging tissues
how can bacteria become antibiotic resistant
- one bacterial pathogen mutates to become antibiotic resistant
- this is not killed by antibiotics.
- they survive and reproduce so population rises
- spreads because people aren’t immune so there’s no effective treatment
what can you do to reduce the rate of development of antibiotic resistant strains
- doctors should not prescribe antibiotics inappropriately, for example treating viral infections or treating non-serious bacterial infections
- patients should have all the antibiotics prescribed to them
- the use of antibiotics on farm animals should be restricted
what is the function of digitalis
heart drug
where does digitalis originate from
foxglove
where does aspirin originate from
willow tree
what is the function of aspirin
painkiller
what is the function of penicillin
antibiotic
where does penicillin originate from
penicillium mould
what do new drugs have to be tested for
toxicity, efficacy and dosage
what is the process of preclinical testing
- done in a lab using cells, tissue and live animals
- after preclinical testing, clinical trial use healthy volunteers then patients.
- very low doses are given at the start then if the drug is safe, more clinical trials are carried out to find the optimum dose for the drug
what is a placebo
a substance that looks like the real drug but doesn’t do anything
why are placebos used in clinical trials
to make sure the drug actually works and people don’t just think it does
what is a double blind trial
both the doctors and volunteers are unaware of who is receiving the real drug and who is receiving the placebo, this is done to avoid bias.
what is a good medicine
effective, safe, stable, easy to take and successfully removed from the body
what are monoclonal antibodies
monoclonal antibodies are produced from a single clone of cells. The antibodies are specific to one binding site on one protein antigen so they are able to target a specific chemical or specific cells in the body
what is the process of obtaining monoclonal antibodies
- mouse is injected with a specific antigen, the immune system responds
- white blood cells called B-lymphocytes produce specific antibodies to that antigen
- tumour cells are able to divide easily but can’t make antibodies
- B-lymphocytes are fused with tumour cells as B-lymphocytes take a long time to divide and it’s hard to arrange the right conditions
- these cells are called hybridoma cells and can make specific antibodies. they are screened to make sure they are producing the correct antibody.
- the hybridoma cells are cloned to get lots of identical cells. these cells now produce the same antibody.
- these antibodies are called monoclonal antibodies because they came from a single cloned cell
- antibodies are then harvested and purified, used for a range of different purposes
what are the uses of monoclonal antibodies
- diagnosis
- treat cancer
- measure hormone levels
- can have fluorescent dye attached to them to detect specific molecules on a cell or tissue sample
why aren’t monoclonal antibodies used as widely
they cause more side effects than originally expected
