1. NOTES – IMMUNE SYSTEM – SPECIFIC DEFENSES
immune system attacks a specific disease causing agent
ANTIGENS
something that triggers an immune response

2. KEY CELLS
Lymphocyte
a type of wbc (white blood cell)

3. B - lymphocyte
produces ANTIBODIES – attach to antigen to destroy bacteria
Antibodies
basic unit of the immune system
shaped like the letter “Y”

4. Specific Immune Response
I. Cell Mediated Immunity
T – cells that directly attack antigens
KILLER T – CELLS cause pathogens to rupture & die
responsible for transplant rejection, destroying certain cancer cells, fungal infections

5. II. Humoral Immunity
PLASMA CELLS (specialized b – cells) release antibodies into the bloodstream when a pathogen enters the body
this process is aided by T – lymphocytes (T – cells) – wbc’s from thymus gland
T – cells help regulate production of antibodies by b – cells
Antibody Production
b – lymphocytes produce one cell that can rearrange its genetic code
this allows for many different types of antibodies

6. can bind to two antigens at once – causes virus to AGGLUTINATE or clump together
phagocyte can then destroy the agglutinated virus
antibodies will do the same thing to bacteria

7. after exposure to certain diseases, the body does not become infected with those diseases again
Immunity
EX: chicken pox
b – cells & T – cells remain capable of producing the same antibodies for life
this is called the SECONDARY IMMUNE RESPONSE
very quick – disease never gets a chance to develop

8. I. Active Immunity
injection of an ATTENUATED or weakened form of a virus or bacteria
Ex: Jenner & smallpox
allows body to produce immunity without contracting the disease first

9. II. Passive Immunity
-- antibodies from another person or artificially produced introduced to protect another person
Ex. Mother’s antibodies passed on to newborn

10. NOTES – IMMUNE SYSTEM DISORDERS
Allergies
results from an “overreaction” of the immune system
immune system produces chemicals called HISTAMINES – cause sneezing, runny nose, etc.
EX: food allergies, bee stings, penicillin, etc
can produce serious allergic reactions
Anaphylactic Shock
massive release of histamine – bronchioles contract – no air into or out of lungs

11. Autoimmune Diseases
occurs when immune system attacks body’s own cells
can be the result of infection – Ex: Rheumatic Fever attacks heart as a result of strep throat
other ex: rheumatoid arthritis, juvenile diabetes, multiple sclerosis

12. What does AIDS stand for?
Acquired Immune Deficiency Syndrome
HIV
Human Immunodeficiency Virus – causes AIDS
retrovirus – genetic info is contained in RNA
begins in Helper T – cells, virus not affected by the immune system
virus makes it impossible for body to respond to disease
virus continually mutates – makes vaccine, medication difficult