Immune system
Chp. 16 (pp. 323-350)
~20,000 genes affect immunity, usually
polygenic or multifactorial traits
Major Structures• Lymphocyte (produce by spleen)
- one kind of white blood cell
- T-cell and B-cell
• Lymph vessels
• Lymph nodes
• White blood cells
• Spleen
• Skin
Function of the system
• The immune system is the system of
specialized cells and organs that protect
an organism from outside biological
influences
• Defends against pathogens and disease
–
Cell surfaces used to recognize “foreign” or
“nonself” surfaces
•
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Autoimmune- immune system attacks individuals
own tissues or organs
Genes encode for
–
•
•
–
initiate immune response
antibodies are proteins which attack foreign molecules
cytokines are biochemicals which attack foreign
molecules
antigens molecules that cause an immune
response
Lymph nodes
•Spleen
-Store blood
-Kill old RBC
-Produce lymphocyte
• AIDS
HIV (human immunodeficiency virus)
infection will lead to immune system
collapse
• HIV usually invades helper T cell, which
begin to produce HIV soon after infection.
• Helper T cell die, the
– immune system gradually weakens
– becomes overwhelmed by pathogens that
would normally detect and destroy.
Diseases associated with that system
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•
•
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Graves’ disease
Multiple sclerosis
Rheumatoid arthritis
Systemic lupus erythematosus (SLE)
- facial skin rash, painful joints, fever,
fatigue, kidney problem, weight loss
• Type I diabetes
One interesting fact
• Allergy is the body’s overreaction to a normally
harmless antigen
• Allergy- causing antigens include pollen, spores,
foods, drugs, and dust mites.
Allergies are caused by our immune
system protecting us too much!!!!!!!!!