B3 - Infection and Response Flashcards
what do pathogens produce that make us feel ill
toxins that damage tissues
what are pathogens
microorganisms which cause infectious disease
how to pathogens infect people
direct contact
water
air
why do viruses cause cell damage
as they live inside cells causing cell damage
what type of disease is measles
viral
measles symptoms
fever
red skin rash
how is measles prevented
most young children are vaccinated against it
how is measles spread
inhalation of droplets from sneezes and coughs
HIV symptoms
flue like symptoms
what can HIV be controlled by
antiretrovical drugs
what does HIV attack
the bodys immune cells
when does AIDS happen
when HIV causes the bodys immune system to become so badly damaged it cant deal with other infections or cancers
how is HIV spread
sexual contact
exchange of bodily fluids
what does TMV affect
many species of plant including tomatoes
TMV symptoms
mosaic pattern of discolouration
what is salmonella
a food posining spread by bacteria ingested in food
how is salmonella prevented
poultry are vaccinated
salmonella symptoms
fever
abdominal cramps
vomiting
diarrhoea
ghonorrhoea symptoms
thick yellow or green discharge
pain during urination
what was gonnorrhoea previosuly treated by
penicilin
how is gonorrhoea spread
sexual contact
how can gonorrhoea be controlled
anitbiotics
barrier contraception
which type of disease is rose black spot
fungal
rose black spot symptoms
purple/black spots develop on leaves
how is rose blackspot spread
water
wind
how can rose black spot be treated
using fungicides or removing and destroying affected leaves
what type of disease is malaria
protist
how is the spread of malaria controlled
preventing vectors from breeding
mosquito nets
how does the skin defend against pathogens
acts as a barrier
secretes antimicrobial substances
how does the nose defend agaisnt pathogenst
structures in the nose dont allow pathogens to go through:
hairs
mucus
they trap particles that may contain pathogens
how do the trachea and bronchi help defend against pathogens
theyre lined with cilia which take the mucus up to the back of the throat where its swallowed
how does the stomach help defend against pathogens
makes hydrochloric acid to kill them
what is phagotocis
when your white blood cells engulf foreign cells and digest them
how do white blood cells produce antibodies
1 - the white blood cell find a foreign antigen they begin to produce proteins called antibodies to lock onto the invading cells so that they can be found and destroyed
2 - the antibodies are produced rapidly and carried all around the body to attach to the antigens
how do vaccines work
introducing a small quantitiy of the dead or inactive forms of a pathogen into the body to stimulate the white blood cells to produce antibodies. if the same pathogen enters the body, the white blood cells can respond quickly and produce the correct antibodies preventing infection
how do antibiotics work
they help to cure bacterial disease by killing infective bacteria inside the body.
why is it difficult to treat viral diseases with drugs
its hard to develop drugs that kill viruses without damaging the body’s tissues.
examples of drugs that were extracted from plants
digitalis - treats heart - foxgloves
aspirin - painkiller - willow
penicilin - mould
what 3 things are new drugs tested for
toxicity
efficacy
dose
describe the process of trialing a drug
1 - drugs tested on human cells and tissues in the lab
2 - testing it on live animals to test for efficacy, toxicity, dosage
3 - tested on human volunteers
describe the clincal trials
1 - drug tested on healthy volunteers to make sure there are no harmful side effects.
2 - drugs tested on people who are suffering from the illness to find optimum dose
3 - double blind trials
how are monoclonal antibodies produced
1 - stimulating mouse lymphocytes to make a particluar antibody.
2 - the lymphocytes are combined with a tumour cell to make a hybridoma cell
3 - the hybrodioma cell is then cloned to produce many identical cells
4 - these cells produce the same antibody which can be collected and purified
how are monoclonal antibodies used in pregnancy tests
1 - the part of the stick you urinate on has antibodies to HCG with blue beads attached
2 - the test strip has more of the antibodies which make HCG stick onto it if present
3 - if pregenant, the hormone and beads binds to the antibodies meaning it turns blue
how can monoclonal antibodies be used to locate or identify specific molecules in a cell or tissue
1 - monoclonal antibodies are made that will bind to the specific molecule being looked for
2 - the antibodies are attached to a floruecent dye
3 - if the molecules are present, the antibodies will attach to them and detected using the dye
why are monoclonal antibodies not as widely used as hoped
as they have many side effects
how can plant diseases be identified
gardening manual or website
taking infected plants to labs to identify
using testing kits which use monoclonal antibodies
what are nitrate ions needed for
protein synthesis - growth
what are magnesium ions needed for
to make chlorophyll
plant physical defenses
cellulose cell wall
tough waxy cuticle on leaves
layers of dead cells around stems
chemical plant defenses
antibacterial chemicals
poisons to deter herbivores
mechanical plant defenses
thorns and hairs deter animals
leaves which droop or curl
mimicry
