Defence mechanisms help the body protect itself against the entry of microorganisms and resulting communicable diseases.
If a microorganism does enter, there are more mechanisms in place to destroy it quickly.
- Skin – a barrier to microorganisms.
- Mucous membranes – present in the respiratory system to trap microorganisms.
- Blood clotting – stops blood escaping and prevents the entry of microorganisms where the skin has been damaged.
The entry of a microorganism may cause us to be sick while our body fights the infection.