Knowledge Organiser chapter 6 - Preventing and treating infection Flashcards
(27 cards)
What system tries to destroy pathogens if they get in the body?
The immune system
What is contained inside a vaccine?
dead or inactive forms of a pathogen
How does a vaccine work?
It stimulates white blood cells to produce antibodies for that pathogen so if an active form enters the body, antibodies are produced quickly
What is ‘herd immunity’
When a large enough proportion of the population are immune to a disease, its spread is much reduced
What do painkillers do?
Relieve symptoms of disease
What do antibiotics do?
Kill bacterial pathogens
What was the first antibiotic called?
Penicillin
Why can antibiotics not be used for viral infections?
They do not kill viruses, only bacteria
Why is it difficult to develop drugs to kill viruses?
Because they live inside your cells, so the drugs would also damage your cells
Why do antibiotics not work on some bacteria?
Antibiotic resistant strains of bacteria are evolving
What plant is the drug digitalis (digoxin) extracted from?
Foxglove
What is digitalis (digoxin) used to treat?
Heart problems
What plant is the drug aspirin from?
Willow
What is aspirin used to treat?
Pain
Where is the antibiotic penicillin from?
The penicillum mould
How are most new drugs made?
They are synthesised by chemists in the lab but the starting point may be a chemical extracted from a plant
What are all new drugs tested for in clinical trials?
Toxicity, efficacy (if they work) and dose
Who are clinical trials tested on?
Healthy volunteers & patients
How are drugs tested before being tested on humans?
In the lab using cells, tissues and live animals
What is a ‘double blind’ trial?
A test where neither the patient or the doctor know if the patient is being given the drug or a placebo
What is a ‘placebo’?
A dummy drug that does not contain any of the medicine being tested
Why are placebos used?
As a control
How is a ‘hybridoma’ made?
Combining a mouse lymphocyle with a tumour cell
How are hybridomas used to make ‘monoclonal antibodies’?
Stimulating the mouse lymphocyte to produce a particular antibody, making it into a hybridoma which will divide and make large amounts of the antibody
