Foundation: B3 - Infection & response Flashcards
Define pathogen.
A microorganism that causes infectious disease
What are the 4 types of microorganisms that can cause disease?
Bacteria, virus, fungi, protist
Other than microorganisms, what other factors can affect health?
Stress, diet, life situation
How do bacteria divide and cause disease?
Binary fission (splitting in half), release toxins
How do viruses divide and cause disease?
Have to divide in a host cell, destroys host cells
Give some examples of communicable diseases.
Any infectious disease
Define a non-communicable disease.
A disease which cannot be spread/passed on
What type of pathogen causes measles?
Virus
Why is measles rare in the UK?
Most children are vaccinated
How is HIV spread?
Bodily fluids eg. blood
Describe the symptoms of tobacco mosaic virus.
Mosaic pattern on leaves/discolouration
How do antibiotics stop bacterial diseases?
Stop the replication process
What type of bacterial disease can be caused by undercooked food?
Salmonella
How can you catch gonorrhoea?
Unprotected sexual contact
Why has gonorrhea become harder to treat?
Antibiotic resistance
What fungal disease causes purple or black spots on leaves?
Rose black spot
How do fungal diseases such as rose black spot transmit from plant to plant?
Spores in the air
What is meant by the term vector?
Organisms that carries and transmits disease eg. mosquito
What type of pathogen is spread by mosquitoes and what disease does it cause?
Protist, malaria
How can you reduce the spread of malaria?
Insect nets, bug repellent, preventing reproduction, anti-malarial tablets
Describe the lines of defence to stop pathogens entering the body.
Skin as a barrier, stomach acid, mucus & ciliated cells in airways
Give the 3 ways white blood cells protect from disease.
Ingest pathogens, produce antibodies, produce antitoxins
How do antibodies work?
They have a specific shape to attach to the pathogen and destroy it.
What is present in a vaccine?
Dead or inactivated pathogen
Describe the concept of herd immunity.
If most of the population is vaccinated, then the few that are not are less likely to come into contact with someone infected
What is the difference between drugs such as paracetamol and penicillin?
Painkillers only treat symptoms, antibiotics kill bacteria to cure disease
Why do antibiotics not work on viral diseases?
As viruses replicate inside cells and we do not want to destroy our own body cells
Where does the drug aspirin originate from?
The bark of willow trees
What drug originates from foxgloves?
Digitalis
Where did penicillin originate from?
Mould
What are the stages in drug testing?
Tests on cell and tissues, tests on healthy volunteers, tests on patients
What three things are drugs tested for before they can be sold?
Toxicity, efficacy, dose
Why is it difficult to develop drugs to treat bacterial infections?
Viruses are inside cells, so medication would destroy body cells in order to attack viruses
How can the development of antibiotic resistant bacteria be reduced?
Complete all antibiotic prescriptions, do not over use antibiotics, reduce the use of antibiotics in farm animals
