B6+B7 Preventing and treating disease and non communicable diseases Flashcards
(38 cards)
What are the 4 main ways bacteria can enter the body
droplet infection
direct contact
ingestion
Through the skin
How does your skin protect you from disease
Acts as a barrier
If the skin is broken your platelets form a clot that dries into a scab
Your skin produces antimicrobial secretions
Healthy skin is covered with microorganisms that act as a barrier
How does hair and mucus protect you from disease
They trap particles that may contain pathogens
Mucus is wafted up to the back of the throat where it is swallowed
Stomach acid then destroys any microorganisms that may have been present in the mucus
What are the 3 roles of white blood cells
Engulf destroy and digest pathogens
Produce antibodies that are specific to that pathogen
Produce antigens
Name 2 physical defences plants have
Tough waxy cuticles or leaves
Layers of dead cells around stems/bark
Name 2 chemical defences plants have
Antibacterial chemicals
Poisons
Name 3 mechanical defences plants have
Thorns and hairs
Leaves that droop or curl
Mimicry
What is an antigen
Protein marker on the surface of a cell
Helps your body identify its own cells
How do you become immune to a disease
A foreign antigen enters the body
The white blood cell produces antibodies which destroy the pathogen
The memory cells remember the pathogen
The next time the pathogen enters the body the memory cells can make the antibodies much faster and in higher quantities
How do vaccinations work
Small amounts of a dead or inactive pathogen are injected into the body
The antigens in the vaccine stimulate your white blood cells to make antibodies which destroy the antigen with no risk of you getting infected
You are now immune because your body can respond rapidly and make the correct antibody as if you have already had the disease
What is herd immunity
If a large proportion of the population are immune the spread of a pathogen is limited
What is the role of painkillers
Relieve symptoms and make you feel better
What is the role of antobiotics
Kill bacterial pathogens by damaging bacterial cell walls without harming your own cells
Where is aspirin found
Willow bark
Where is digitalis found
Fox gloves-Treatment for heart conditions
Why do we test drugs
To test they have the following properties:
Efficacy-Cures the disease
Safe-not toxic and has no side affects
Stable-Can be used under normal conditions
What are the steps of testing drugs
Preclinical testing-Lots of possible drugs are made to target a disease and are tested for efficacy and toxicity on cells, tissues and organs, the small number of chemical which pass are then tested on animals
Clinical Trials-Low doses are given to healthy volunteers, if it is safe then it is tested on larges sample sizes
What is a placebo
A version of the drug that does not contain the active ingredient
What are double blind trial
Half the patients get the real drug, half the patients get the placebo, neither patients nor doctors know who receives what
Shows if drug is actually effective
Why are antibodies useful
They bind to specific molecules meaning they can be used to locate specific cells in the body, bind to and label specific molecules and be used in diagnostic testing
How are monoclonal antibodies made
A mouse in injected with a specific antigen
The WBC in the mouse produce antibodies
The antibodies are fused with human tumour cells to form a hybridoma
The hybridoma divides rapidly to make many WBC
The monoclonal antibodies are collected and purified
What are the uses of monoclonal antibodies
Pregnancy tests
Cancer tratments
How are monoclonal antibodies used in pregnancy tests
The monoclonal antibodies used bind to HCG which is a hormone made only in pregnancy
How are monoclonal antibodies used to treat cancer
MCA bind to cancer cells triggering an immune response to destroy cancer cells
MCA block receptors on cancer cells which stops them growing
MCA carry drugs/radioactive substances to attack only cancer cells
