B6 - Preventing and treating disease Flashcards
What are the proteins on the surface of a cell called
antigens
How do antibodies kill pathogens
white blood cells make antibodies that join to antigens and inactivate them
What is the process of immunisation
a vaccine containing dead or inactive form of disease is injected
- immune system is stimulated and produces antibodies
- these are stored by memory cells
What is the function of memory cells
remember the antibodies for a particular pathogen sp they can be produced quickly
What does the MMR vaccine protect against
measles, mumps, rubella
What is herd immunity
the idea that if a large proportion of the population is immune, then the pathogen will rarely spread even if some people aren’t immune
What are the function of painkillers
- what are two common examples
relieve pain
- aspirin and paracetamol
What are some drugs that kill bacteria outside the body
- why can’t we use them
antiseptics and disinfectants
- they are too poisonous in the body
What drugs are used to kill bacteria in the body
antibiotics
how to antibiotics work
damage bacterial cells without damaging human cells
How can antibiotics be effective really fast
direct injection into bloodstream
Why are antibiotics not effective against viruses
viruses live and reproduce inside other cells. It is hard to develop drugs that kill onlythe virus
Why are some bacteria not able to be killed by antobiotics
they have mutated to become resistant
What were drugs traditionally extracted from
- what is used now
plants or microorganisms e.g. moulds
- adapted chemicals from plants, microorganisms and animals
What are two common drugs extracted from foxgloves
- what impact do they have on the body
digitalis and digoxin
- helps strengthen the heartbeat
what is the issue with lots of traditional medicine
they are actually poisonous
What does aspirin originate from
a compound in the bark of willow trees
How was penicillin discovered
- Fleming left the lid off of one of his moulds of bacteria.
- a clear ring had formed in the jelly
- he realised something killed the bacteria
- he called that substance penicillin
- 10 years later Chain and Florey extracted penicillin
who discovered penicillin
alexander fleming
What mould is penicillin from
penicillium
How are most drugs made nowadays
synthesised in the pharmaceutical industry
What are the three things that must be measured for in new drugs
- toxicity
- efficacy
- dosage
What are the stages of trials for new medicine
preclinical - animals, tissues, cells
clinical - on healthy people, infected, volunteers
What are the stages of a double blind trial
some people are given a placebo, some have the actual drug. Neither the patient nor the doctor knows which is which. health is monitored carefully
What happens after a medicine has been confirmed in a double blind trial
peer review, the most effective and cost-efficient ones are used
What are hybridoma cells
combining mice cells with cancer cells
What are monoclonal antibodies
proteins used to target particular cellsor chemicals
What cells are combined for monoclonal antibodies
T-lymphocytes and cancer cells to make hybridomas, which divide fast and produces antibodies. These are cloned to make monoclonal antibodies
What are 5 common uses of monoclonal antibodies
- pregnancy tests
- diagnosis of diseases
- monitoring levels in the body
- research for molecules
- treating disease
How to pregnancy tests work
monoclonal antibodies bind to HCG (produced in pregnancy) if it is present and a colour change occurs
how do monoclonal antibodies discover disease
they are made to bind to specific antigens, and carry markers which makes it easy to see where they have collected. This is used to detect problems
How to drug tests work
monoclonal antibodies bind to the drug if present
What are three ways monoclonal antibodies can be used to kill cancer cells
- direct use of antibodies to trigger immune system to destroy cancer cells
- using monocolonal antibodies to block receptors on the surface of cancer cells which stops them growing and dividing
- carry drugs or radioactive substances for radiation therapy
What are the benefits of using monoclonal antibodies
only bind to a specific pathogen
- can produce lots of them
What are the disadvantages of using monoclonal antibodies
- costly
- not widely available
- mouse cells cause side effects
- producing correct ones are hard
