biology: infection and response

what is a malignant tumour?

• can metastasise and travek through blood

• more dangerous

• cancerous

what is a benign tumour?

• stays in one place

• contained in membrane

• not cancerous

what do painkillers do?

• relieve pain and reduce symptoms

• doesn't treat cause

what do antibiotics do?

kill bacteria

where does aspirin come from?

willow

what type of drug is aspirin?

painkiller

where does digitalis come from?

foxgloves

what is digitalis used for?

to treat heart conditions

who discovered penicillin?

alexander fleming

how was penicillin discovered?

• alexander fleming had mould (penicillium) growing on petri dish

• noticed area around the mould was free of bacteria

why do plants need nitrate ions? what happens when they don't have enough?

to make proteins for growth

why do plants need magnesium ions? what happens when they don't have enough?

• to make chlorophyll for photosynthesis

• lack of this causes chlorosis and yellow leaves

what are the common signs of plant disease?

• stunted growth

• abnormal growth

• decay

• spots on leaves

• discolouration

what are examples of physical defences on plants?

• waxy cuticle (provided barrier to stop pathogens)

• cell walls made from cellulose (forms barrier against pathogens)

• layers of dead cells around stems (bark on trees - stops pathogens)

what are examples of chemical defences on plants?

• produce antibacterial chemicals (mint)

• produce poisons (foxglove

what are examples of mechanical plant defences?

• thorns/hairs stop animals eating them

• mimic other animals to trick predators

• droop or curl when something touches them

what is the process for producing monoclonal antibodies?

• inject mouse with specific antigen

• immune response happens in mouse

how do vaccines spread against future infections?

• weak version of pathogens injected

• lymphocytes detect antigen on surface of pathogen and produce specific antibodies to destroy pathogen

• memory cells remember antigens

what is efficacy and toxicity?

• whether drug works with desired effects (efficacy)

• how harmful a drug is (toxicity)

what is dosage and optimum dosage?

• concentration that should be given and how often

• dose of drug that is most effective with least side effects

what is a placebo? why are they used?

• a fake drug that has no effects on body

• used to see actual difference drug amkes

what is a double blind trial? why are they used?

• both patient and doctor don't know who has placebo

• used so doctors aren't influenced by knowledge

what are the pros and cons of vaccines?

pros - helped control communicable diseases

how does the skin

mucus and stomach prevent pathogens?

what are the the functions of the blood cells that make up the immune system?

white blood cells - make up immune system phagocytes - engulf and destroy pathogens (phagocytosis)

• lymphocytes - some produce antitoxins

how do antibodies and antitoxins fight against pathogens?

antibodies - produced by lymphocytes

why is developing drugs to fight against viruses difficult?

viruses use body cells to reproduce

why is it important to finish a course of antibiotics?

bacteria can mutate to become less resistant to antibiotics

what are the advantages and side effects of monoclonal antibodies?

advantages - can only bind to specific antigen or chemical

how are monoclonal anti does used in labs?

• test samples for specific pathogens

• bind to hormones to measure levels in blood

how are monoclonal antibodies used to treat cancer?

• tumour markers are present on cancer cells

what is a pathogen?

a microorganism that causes disease

what is a communicable disease?

disease that can be spread

what are the 4 types of pathogen?

• bacteria

• virus

• fungi

• protists

how do bacteria make you feel ill?

producing toxins that damage body cells

how do viruses make you feel ill?

use body cells to reproduce

what type of cells are protists?

eukaryotic

what is a vector?

an organism that carries a disease

what is hyphae?

thread like structure that can penetrate skin and cause disease

what ways can pathogens be spread?

• water

• air

• physical contact

what type of pathogen causes measles? how is it spread?

• virus

• spread by droplets from an infected persons sneeze or cough

what are the symptoms of measles?

red rash

what pathogen causes hiv? how is it spread?

• virus

• spread through sexual contact and exchanging bodily fluids

what are the symptoms of hiv?

initially flu like symptoms

how can a person with hiv be treated?

antiretroviral drugs

when does hiv become aids?

when the body is too weak to fight infections

what pathogen causes tobacco mosaic virus?

virus

what are the symptoms of tobacco mosaic virus? how do these effect plant?

• discolouration on leaves

• discolouration affects photosynthesis and growth

what pathogen causes rose black spot? how is it spread?

• fungus

• spreads through water/wind

what are the symptoms of rose black spot? how can it be treated?

• black spots on leaves

what pathogen causes malaria? how is it spread?

• protists

• spread by infected mosquitoes

what are the symptoms of malaria? how can it be prevented?

• fever

• insecticides

what pathogen causes salmonella? how is it spread?

• bacteria

• spread through contaminated foods

what are the symptoms of salmonella? what causes these?

• fever

what pathogen causes gonorrhoea? what are the symptoms?

• std caused by bacteria

• pain when urinating

how is gonorrhoea spread? how can it be treated?

• sexual contact

• treated with antibiotics

how can the spread of diseases be prevented?

• hygiene

• destroying vectors

• isolate infected

• vaccination

what is a risk factor?

something that increases your risk of getting a non-communicable disease

what causes cancer?

uncontrolled cell growth due to mutations open dna during mitosis

what is mitosis? what is it used for?

• cell division

• used for growth and repair

what risk factors increase a persons chance of getting cancer?

• smoking

• obesity

• direct uv exposure