1	The IMMUNE SYSTEM The Body’s Defenses Intro 2009: Swine Flu http://news.yahoo.com/s/time/08599189431400 or ..\..\..\..\COURSES\AP BIO\articles\Diseases and conditions\2009 SWINE FLU Article Mexico.doc
2	Defense against pathogens Pathogen = an organism or virus that causes a disease.
3	Bacteria vs. Viruses Bacteria Prokaryote CELLS-unicellular Living Has metabolism Viruses Not cells Not living, can NOT reproduce on their own Consist of DNA/RNA and a protein coat
4	Bacteria vs. Viruses: Treatment and Defense What do antibiotics fight? Antibiotics destroy the cell wall. Happens in Bacteria only, NOT Viruses Why not viruses?? They do not have a cell wall. Some antiviral medications are available, but usually you have to let the illness pass on its own. Your body defends against bacteria and viruses. Let’s see how.
5	Lines of Defense
6	Nonspecific Defense Mechanisms…… 1^st lines of defense… Skin and mucous membranes (tears/ear wax) Stomach acidity
7	Specific Immunity Lymphocyctes (a type of white blood cells)- White blood cells defend the body. Two types B Cells (develop in bone marrow) T Cells (develop in thymus) Antigen: a foreign molecule that causes a response by lymphocytes Where might you find an antigen? Antibodies: proteins in body that fight pathogens by binding to antigens. Very specific.
8	Overview of specific immune responses C:\Documents and Settings\BBAUGHMAN\Desktop\bio powerpoints\Chapter 39 BDOL IC Animations: Animation of immune system OK…but not great
9	Antibody Action
10	Types of White Blood Cells Phagocytes (Macrophages): Eat pathogens by endocytosis and present antigens to other white blood cells. B lymphocytes: Produce antibodies T lymphocytes: Helper T cells: help activate B cells and “killer” T cells Killer T cells: destroy infected cells. Memory Cells B or T cells that “remember” the antigen. Why you don’t get sick twice by the same germ
11	Helper T Cell, Cytotoxic T cell Activity http://highered.mcgraw-hill.com/sites/0072437316/student_view0/chapter48/animations.html
12	Induction of Immune Responses Primary immune response: Production of lymphocytes and antibodies the 1st time the body is exposed to an antigen Secondary immune response: stronger, faster immune response if the individual is exposed to the same antigen at some later time~ Immunological memory
13	Immunity in Health & Disease How to get immune: immunity by recovering from disease What is a vaccine? A shot given to a patient containing the weakened/dead virus/bacteria to stimulate an immune response. Vaccination: produces a primary response. Produces memory cells for the disease, so when you come in contact with the disease you do not get it.
14	Vaccination: Benefits Discussion Discussion: Benefits: Epidemic/pandemic/death prevention Eradication of fatal/debilitating diseases (ex. smallpox) Reduced disability due to diseases (ex. Blindness and deafness in babies due to rubella infection of their unvaccinated mothers.) Vaccines = carefully tested for safety. Serious adverse reactions (allergic) are very rare. Dangers: Some controversial concerns… (discussion) “The medical and scientific communities have carefully and thoroughly reviewed the evidence concerning the vaccine-autism theory and have found no association between vaccines and autism.” Citation: http://www.cdc.gov/Features/AutismDecision/
15	AIDS Caused by HIV (human immunodeficiency virus) Infects several types of white blood cells Causes a reduction in the # of active lymphocytes and an inability to produce antibodies. Weakens the immune system Normally die not from AIDs, but from the flu or common cold.
16	"Discuss cause" Discuss cause, transmission, social implications. UN Article on AIDS orphans (2004) http://www.unaids.org/bangkok2004/GAR2004_html/GAR2004_05_en.htm Same article in word document
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