n Flashcards
What is the main barrier against pathogens?
The skin is our main barrier against pathogens getting in. The vast majority of pathogens cannot get through the skin at all.
What happens to the skin when there is a cut or wound?
The skin scabs over to provide a quick barrier.
How does the nose help trap microorganisms?
The nose has hairs and mucus to trap microorganisms so they don’t get any further than the nose.
What happens to mucus if you don’t blow your nose?
The mucus ends up in the back of the throat and you swallow it, which is harmless because the stomach acid kills any microorganisms.
What role does mucus play in the trachea and bronchi?
Mucus in the trachea and bronchi traps microorganisms that are breathed in.
What does the stomach produce to kill microorganisms?
The stomach produces hydrochloric acid (at pH 2), which kills most microorganisms that are swallowed.
What triggers the immune system to respond?
The immune system responds if pathogens enter the body properly, i.e., if they get into the bloodstream.
What are the most important cells in the immune system?
The most important cells in the immune system are the white blood cells.
What is phagocytosis?
Phagocytosis is the engulfing and digesting of pathogens by white blood cells, destroying the pathogens.
What do white blood cells produce to combat pathogens?
White blood cells produce chemicals called antibodies that bind to pathogens and destroy them.
What is the specificity of antibodies?
Antibodies are specific, meaning only one particular antibody type will bind to one particular pathogen.
What do some pathogens produce that are neutralised by antitoxins?
Some pathogens, especially bacteria, produce poisonous toxins that are neutralised by antitoxins.
What are antitoxins?
Antitoxins are another sort of chemical produced by white blood cells that are specific to specific toxins.
