B6 Preventing and treating disease Flashcards
What does every cell have on its surface?
unique proteins called antigens
The antigens on the microorganisms that get into your body are…
…different to the ones on your own cells
Your _____ system recognises that the ____ on the micro-organisms that get into your body are _____ to the ones on your __ cells
i) immune
ii) antigens
iii) different
iv) own
What happens after your immune system recognises the difference between the antigens on the micro-organisms that enter your body?
your WBCs make specific anti-bodies
What do antibodies do?
join up with antigens and inactivate or destroy that particular pathogen
What can some of your white blood cells do?
memory cells ‘remember’ the right antibody needed to destroy a particular pathogen
What happens if you meet the same pathogen you have before?
the memory cells can make the same antibody very quickly to kill the pathogen, so you become immune to the disease
Why do you get ill the first time you meet a new pathogen
there is a delay while your body sorts out the right antibody needed
Some pathogens can make you seriously ill very quick;y. Give an example
meningitis
Why can you die very quickly by serious diseases?
the disease affects the body before it manages to make the right antibodies
What does immunization involve?
giving a vaccine made of a dead or inactivated form of a disease-causing microorganism
What do dead or inactivated form of a disease-causing microoganism stimulates?
your body’s natural immune response to invading pathogens
What happens in a vaccination?
- small amount of dead/inactive forms of a pathogen is introduced into the body
- stimulates while blood cells to product antibodies needed to fight the pathogen and prevent you from being ill
Why do vaccinations work?
if you meet the same, live pathogen, your white blood cells can respond rapidly
- make right antibodies
- just as if you already had the disease
What do doctors use vaccines to protect us from?
against both bacterial diseases and viral diseases
Name two bacterial diseases
tetanus and diphtheria
Name three viral diseases
polio, measles and mumps
What is herd immunity?
if a large proportion of the population is immune to a disease, spread of pathogen reduces and may even disappear
What is a drawback of herd immunity?
it will take money and determination
Often medicine doesn’t affect the pathogen that is causing the problems. What does it do?
eases the symptoms and makes you feel better
Give examples of drugs that are very useful pain killers?
aspirin and paracetamol
Painkillers help relieve but…
have no effect on the viruses that have entered your tissues and made you feel ill
What are antiseptics and disinfectants used for?
to kill bacteria outside the body; far too poisonous to use inside your body
What are the drugs that have really changed the treatment of communicable diseases?
antibiotics
What are antibiotics?
Medicines that can work inside your body to kill BACTERIAL pathogens
When were antibiotics first widely available?
1940s
An example of antibiotic?
penicillin
how do antibiotics work?
killing the bacterua that cause disease whilst they are in your body
What do antibiotics do?
damage the bacterial cells without harming your own cells
What form do antibiotics take
a pill/syrup
-very ill, antibiotics may be put straight into your bloodstream
Why are antibiotics sometimes put straight into the bloodstream?
make sure they reach the pathogens as soon as possible
Some antibiotics…
Others are…
…kill a wide range of bacteria
…are very specific and only work against particular bacteria
Specific bacteria should be treated with…
the specific antibiotic that is effective against them
What do viruses do?
reproduce inside the cells of your body
Why is is extremely difficult to develop drugs that will kill viruses?
risk of famaging the cells and tissues of your body as the same time
Drawback of antibiotics?
cannot kill viral pathogens
-strains of bacteria that are resistant to antibiotics are evolving
Traditionally, where were drugs extracted from?
plants or microorganisms such as moulds
How do scientists make more effective drugs nowadays?
often adapt chemicals from microorganisms, plants and animals
What is digitalis and digoxin?
one of several drugs extracted from foxgloves that have been used since the 18th century to help strengthen the heartbeat
What do doctors still use digoxin for?
older patients with heart problems
Large amounts of these chemicals in drugs can act as?
poisons
aspirin originates from?
a compound found in the bark of willow trees
What sort of properties to aspirin have and when were they recorded?
anti-flammatory and pain-relieving properties
-400BC
In 1897, what did Felix Hoffman do?
synthesised acetyl salicylic acid
What is aspirin and what does it do?
acetyl salicylic acid
-relieves pain and inflammation better than willow bark but has fewer side effects