IMMUNITY NOTES.
, CATEGORIES OF DEFENCE MECHANISMS
1. Non-specific defence mechanisms.
• Protect against any of an enormous range of
possible dangers.
2. Specific defence mechanisms/ immunity.
• Resistance is directed against only one particular
invader.
• Immunological memory develops, which confers
long-term immunity to specific infections.
• An antigen is anything that stimulates an immune
response.
,NON-SPECIFIC DEFENCE
MECHANISMS
, • These are the first lines of general defense;
they prevent entry and minimize further
passage of microbes and other foreign
material into the body.
• There are four main non-specific defense
mechanisms:
Defence at body surfaces
Phagocytosis
Natural antimicrobial substances
The inflammatory response