Physical and chemical barriers Flashcards
(4 cards)
1
Q
What is a physical barrier?
A
A structure that stops something from entering a certain area. Pathogens find it difficult to get past these defences. eg. Skin - it is very thick and covers most of the body.
2
Q
What is a chemical barrier?
A
The use of chemical compounds to defend against attacks. These react with substances in the pathogen and this kills the pathogen or makes them inactive.
3
Q
List some chemical barriers
A
tears, stomach acid, lysozyme
4
Q
List some physical barriers
A
scabs, eyelashes, hairs in the nose, skin, trachea (cilia)
