5.7 Human Defense Responses Flashcards
1
Q
Explain how the body seals a cut to prevent disease
A
- When you bleed, platelets in your blood set up a chain of events to form a blood clot
- blood clot dries to form a scab
- scab forms a seal over the cut
stopping pathogens entering the body through the wound
2
Q
What does the skin do
A
- acts as a barrier, preventing bacteria and viruses reaching the tissue beneath
- produces antimicrobial secretions to destroy pathogenic bacteria
- healthy skin is covered with microorganisms that help keep you healthy acting as an extra barrier to the entry of pathogens
3
Q
What does the nose do to defend against pathogens
(trachea and bronchi)
A
- Nose is full of cilia and produces mucus
- Traps pathogens in the air
4
Q
What does the cilia do
A
tiny hair like projections
cells beat to waft mucus up to back of the throat where it is swallowed
5
Q
what does stomach do to prevent pathogens
A
- produces hydochloric acid to destroy microorganisms in the mucus you swallow
- also destroys majority of pathogens in food and drink
6
Q
How do white blood cells defend against pathogens?
A
- engulf bacteria
- produce antibodies, target particular bacteria and destroy them
- produce antitoxins, getting rid of the toxins released by pathogens
7
Q
How does wbc ingesting pathogens protect you against disease?
A
The pathogens are digested and destroyed so they can’t make you ill
8
Q
How does wbc producing antibodies protect you from disease?
A
- antibodies target particular bacteria or viruses and destroy them
- you need a unique antibody for each type of pathogen
- when wbc have produced antibodies once for a particular pathogen, they can be made quickly if pathogen gets into body again
- this stops you getting the disease twice
9
Q
How does producing antitoxins protect you against disease?
A
Antitoxins counteract the toxins produced by pathogens
