infection and response Flashcards
what are pathogens
this are microorganisms that can enter the body and cause disease
what are the types of pathogens
virus, bacteria, protists, fungus
how do viruses make us feel ill
virus invades the host cell and then the virus uses the host cell machinery to makes copies of itself inside the host cell and then burst releasing new viruses. this then damages the cell
give an example of a virus
HIV, Tobacco mosaic virus
how does bacteria make us feel ill
Bacteria may produce toxins that damage tissues and make us feel ill and they reproduce rapidly
what is an example of a bacteria
salmonella causes food poisoning
how do protists make me feel ill
they have vectors that tansmit the pathogen onto the host
what is an example of a disease associated with protists
malaria
how does fungus makes us ill
Fungi release spores into the air that can be inhaled.
Fungi spores can land on the skin and cause an infection
example of fungus
rose black spot
how can pathogens spread
water- drinking or bathing with dirty water
air- breathing in air droplets, coughing, sneezing
direct contact- touch of skin
what are the symptoms of salmonella and how can they spread
Fever,stomach cramps,Chills Headache, vomiting
and they can spread through uncooked or contaminated food
what are the symptoms of gonorrhoea and how does it spread
bacteria. pain when urinating, yellow discharge from penis or vagina, painful sex
unprotected sex, mother to child
what are the symptoms of HIV and how can it be spread
flu like symptoms. spread through sex, sharing needles, mother to child
what are the symptoms of measles and how can it spread
rash, fever, cough
it can be spread through breathing- in air droplets
what are the symptoms of rose black spot and how are they spread
Black or purple spots on the upper surface of leaf, yellowing leaves, premature leave drop
they can be spread through primarily spread from leaf to leaf and plant to plant by wind
what are the symptoms of tobacco mosaic virus and how can they spread
yellow leaves, mosaic pattern on leaf
spread through: TMV can spread when people who have handled infected plants touch healthy plants, Plant-to-plant
symptoms of malaria and how they are spread
fever, chills, vomitting, diarrhoea,
spread through female anopheles mosquito as vectors
how can we prevent the spread of pathogens
isolation, vaccination, hygiene
how does the nose act as a non specific defense system for the body
nose- mucus traps microbes
how does the mouth act as a non specific defense system for the body
contains good bacteria that stop pathogens from growing.
how does the trachea and bronchi act as a non specific defense system for the body
mucus traps microbes and cilia sweep them away.
how does the stomach act as a non specific defense system for the body
hydrochloric acid kills bacteria
how does the reproductive system act as a non specific defense system for the body
vagina and urethra are very acidic
how does the skin act as a non specific defense system for the body
acts as a barrier and secrets antimicrobial compounds which can kill or stop the growth of pathogens.
when you are wounded the skin forms scabs
how does the tears in the eyes act as a non specific defense system for the body
they wash out pathogens and c ontain lysosyme
describe the three ways the white blood cells destroy pathogens
the white blood cell engulfs the pathogen and destroys it (phagocytosis)
the white blood cell produces antitoxins that neutralise the toxins.
the white blood cells produce antibodies that bind to the antigen on the pathogen and destroys the pathogen(lymphocytosis)
what is a vaccination
it’s made of dead or weakened pathogens.
how do vaccines work
when the dead pathogens are injected into the body the white blood cells (lymphocytes) produce antibodies that bind to the natigens and destroys the pathogen. The lymphocytes also create memory cells so that upon second exposure to the actual pathogen the white blood can remember the antibodies needed to destroy the pathogen and then the white blood cells produce antibodies at a faster rate to kill the pathogen.
what is herd immunity
when a large proportion of people are vaccinated against pathogens this would reduce the spread of the pathogens
what are antibiotics and how do they work
drugs that treat bacterial infections and they work by didtrupting the cell wall of the bacteria
why cant we use antibiotics for viruses
viruses are too small and can hide inside their host cell
where is digitalis extracted from and it’s use
fox gloves and is used in treatment of heart conditions
where is aspirin extracted from and it’s use
willow and is a pain killer
where is penicillin extracted from and it’s use
mold and it’s an antibiotic
what is antibiotic resistance
when a bacteria becomes resistant to antibiotics
causes of antibiotic resistance
taking antibiotics too often
not finishing course of antibiotics
what are pain killers
they relieve pain symptoms
Describe how antibiotic resistance works
They are variety of bacteria in the body. What’s the antibiotic is administered into the body it starts killing off the susceptible bacteria slowly until he kills all the susceptible bacteria. You are now left with the resistant bacteria. Once you stop taking the antibiotics the resistance bacteria remain there and they start to reproduce into lots of resistant bacteria and when you take antibiotic again it has no effect on the bacteria
What are monoclonal antibodies
These are antibodies that can bind to one specific antigen and a produced from clones of hybridoma cells
How Am are monoclonal antibodies produced
You inject a mouse with an antigen and then you extract B-lymphocytes from the mouse which would produce the antibody that you want to use.
You fuse the B-lymphocytes and tumor cells to form hybridoma cells. You then clone the hybridoma cells.
And this cloned hybridoma cells produce lots of antibodies and then you collect and purify.
Explain the use of monoclonal antibodies in pregnancy tests
Monoclonal antibodies are used to check whether there is HCG in a woman’s urine to determine if they are pregnant.
If the person is pregnant they will have hCG and their urine and if they are not pregnant they won’t have hCG In their urine
Explain monoclonal antibodies in positive pregnancy test
If the person is pregnant the hCG and their urine will bind to the antibodies on the blue beads on the test kit so when the blue beads flow over the test strip hcg they are carrying binds binds to the fixed antibodies as well and the beads get stuck in one place by trapping lots of blue beads the entire strip appears blue
Explain monoclonal antibodies in negative pregnancy test
Since the person is not pregnant there is no hCG in the urine which means there is not in to bind to the antibody on the test kit so they’ll be no color appearing
Explain monoclonal antibodies in a pregnancy kits control window
The blue dyed beads with hCG attached to the antibodies are going to move down through the first test strip and go to the control window where it will bind with the antibodies in the control window causing the control window to turn blue even if the test is positive on negative.
If there is no color change in the control window it means that the test hasn’t worked
Explain monoclonal antibodies in treating diseases specifically cancer
The monoclonal antibody binds with the anti cancer drug and then the antibody binds with the antigen on the tumor cells effectively killing the cancer cells
Explain monoclonal antibodies in Elisa test (drug test)
We add the sample which contains the antigen to the well .we wash the well several times to remove any antigens that didn’t stick to the well. we then add an antibody specific to the antigen .we now wait for the antibody to stick to the antigen and then we wash to remove any antibodies that didn’t stick .we then add the second antibody which would bind to the first antibody. we wash again to remove any unbound second antibody. the second antibody had an enzyme we now add the substrate for that enzyme the enzyme converts the substrate into a colored product molecule if the if the test is positive there will be a color reaction.
what are the features of a good medicine
efficacy- effective
safe
not toxic
optimum dosage
what are the stages of drug testing
pre clinical and clinical trials
what are the preclinical trials, explain this with the aid of the stages
stage 1 - drugs are tested on human cells and tissues.
stage 2- drugs are tested on live animals(mammals). this tests efficacy, toxicity and dosage on the drug
what are clinical trials, explain with the aid of the different stages
Stage 1- give drugs to a small group of healthy volunteers at a low dosage and increase the dose slowly to find the optimum dose.
Stage 2- give drugs to people sick with the illness at a low dose and then slowly increasing the dose to find optimum dosage and this time with a larger sample.
Stage 3- only carried out on medicines that have passed stage 1&2 of the clinical trials. This sample size increased again, then further testing is done to see if it’s effective.
Stage 4- the safety, side effects and effectiveness on medicine continue to be studied while it’s being practiced.
what is a placebo
fake drug
why do we have double blind trials
to avoid experimental bias
what has to happen before the results of drug testing and drug trials are published
they have to be peer reviewed
what is a blind trial
only the doctor knows who is taking the placebo or drug
what minerals do plants need
nitrates, magnesium
what is a double blind trial
doctor and patient don’t know who is taking the placebo or drug
what do nitrates do for plants and what are the symptoms that the plant expriences when the plant is deficient of nitrate
to make protein and therefore for growth.
stunted growth
what does magnesium do for plants and what are the symptoms that the plant expriences when the plant is deficient of magnesium
making chlorophyll needed for photosynthesis
chlorosis (yellowing of leaves)
what are the symptoms of plants getting a disease
.stunted growth. spots on leaves. patches of decay. abnormal growth. discolouration. malformed stems or leaves
how plant diseases can be identified
through gardening manuals
taking infected plants to a lab to identify pathogen
using monoclonal antibodies to identify pathogens
what are the physical defenses of a plant
waxy cuticle- barrier to stop pathogens from entering
cell walls (cellulose)- physical barrier
have layers of dead cells around their stem- barrier
what are the chemical defenses of a plant
produce antibacterial chemicals that kill bacteria
other plants produce poisons which can deter herbivores
what are the mechanical defenses of a plant
have thorns or hairs
leaves that droop or curl
some plants can mimic
