Human Immune System

From ZuluNotes - Free Leaving Cert Notes

General defence system: -is non-specific. -Acts against all pathogens. -2 parts to the general defence system: The first: Consists of skin,mucous,membranes & their secretions! -These prevent the entry of all pathogens. -The second: Consists of white blood cells & chemicals that destroy any pathogens that penetrate the body!

• Pathogens: Are foreign bodies & cells that cause disease.

-The Specific Defence System: (Immune system) -Attacks particularly pathogens ,either by producing antibodies against them or killing infected cells.

• Antigen: a foreign molecule that stimulates production of antibodies.
• Anibody: A protein produced by lymphocytes in response to an antigen.