L19- Immune Flashcards
Immune system
Includes cells, processes & chemicals that keep us disease free
What causes disease?
- Pathogens: bacteria, viruses, parasites
- Cancer cells
Immunity
Ability to recognize and eliminate foreign invaders or abnormal “self” cells that cause disease ( cancer cells)
Immunology
Study of immune processes
Big picture function of immune system
Keep invaders out!
- external body surface- cutaneous membrane
- internal body surface - mucous membranes
If invaders get in what does the immune system do
- eat them = cells phagocytize
- shoot them = cells secrete/ inject chemicals into them
What are the 2 divisions of the immune system?
Nonspecific and specific
Nonspecific immune system
Born with it (innate)
- involves: WBCs ( not lymphocytes), chemicals, processes that attack any bacteria, viruses, cancer cells, virally infected cells
Specific immune system
- built through exposure to pathogens (acquired)
Involves: B & T lymphocytes
- clones B &T lymphocytes
- have ability to recognize all foreign antigens
Antigens
Molecules on a cell that triggers immune cells in a host
Antigens include…
- Molecules on the surface of a bacteria, virus, virally infected cell, cancer cells
- toxins secreted by bacteria
- Molecules on cells of tissue grafts from a donor
Autoimmunity
Attack on “self” cells
Allergy
Reaction to nonpathogenic substances
Immune deficiency
Immune system not functioning well
What are the primary lymphatic organs
Thymus & red bone marrow