The immune system Flashcards
Phsical barrier against pathogens would be …
Skin it secretes oils and microbial substances which kill the pathogens
It covers the body physically preventing pathogens from entering
Also tears
How is our nose a physical barrier the next defence after it?
They have lots of little hair and mucus which can trap the pathogen or any other particles
If they manage to get through they’re going to have to go through the trachea or the oesophagus
Tracea and bronchi is all covered in a layer of mucus
they also contain cila which moves the mucus to trap particles to thr back of the throat where we can swallow it
What happens to the pathogen filled stomach?
Our stomach produces hydrochloric acid that bring the PH of the stomach down to 2 which is so acidic it kills petty pathogens
What are white blood cells?
Cells that patrol our body circulating our blood and tissue
What is phagocytosis?
Certain white blood cells can directly engulf pathogens by tracking the pathogens down binding to them and then engulfing them and then destroy them
A phagocyte engulfs and destroys a pathogen
What do white blood cells produce?
Anti-toxins which are small molecules that can bind and counteract these toxin produced by pathogens
What are antigens?
Substances that our immune system detects as being forgein
Unique protein markers that are on the surface of our cells
What are antibodies?
Small proteins made by our own white blood cells that can lock onto fergein antigens and then act as signals to tell our white blood cells to come and destroy them
What is the role of the immune system?
To detect and destroy pathogens
How do antibodies work?
Each of our antibodies is specific for a paticular antigen so if they can bind a particular antigen it won’t be able to bind others
Once our immune system know which of our antibodies can bind the pathogens tis starts producing loads of them and remembers it for next time so if were attacked by a pathogen in the future then our body will start producing so many antibodies so quickly that it will destroy all the pathogens before they get the chance to develop
What are antitoxins ?
Antitoxins are small proteins produced by white blood cells that bind and neutralise the toxins produced by bacteria
What is the difference between a comunicable and non-comunicable disease?
A communicable disease is caused by pathogens which can pass from one person to another whereas a non-commuicable disease is caused by a problem in the body so can’t be passed
