2. The Immune System Anatomy and Physiology

3. Immune System Your body’s protection against pathogens (disease causing agents) Two major categories of defense: Non-specific and specific

4. Immune System Non-specific defenses are general, and will work against any pathogen Species resistance, mechanical barriers, chemical barriers, inflammation, phagocytosis

5. Immune System Specific defenses fight off only one particular pathogen Lymphocytes specialize and become T cells and B cells T cells activate B cells B-cell Activation B cells produce antibodies; the single most effective protection

6. Antibody structure Y shaped Variable part fits only one antigen Very specific

7. Antibodies on B cells

8. Immune System Antibodies are made in response to a specific antigen Takes a while to figure out the exact shape to fit the antigen Once made, memory cells will be kept for future exposures

9. Immune System Memory cells explain why you don’t get the same disease twice Some common illnesses, such as cold and flu, are really different mutated forms of the virus. Each time takes a different antibody

10. Immune System Vaccines: are killed or weakened antigens They cause you to make the antibodies and memory cells without you getting sick They are ready if you are ever exposed

11. Type of Immunity Active: You make the antibodies in response to an antigen Passive: Already made antibodies are given to you—mother to baby; some injections for illness

12. Type of Immunity Naturally acquired: you came across the pathogen naturally (got sick) Artificially acquired: a vaccine; you stimulate the exposure on purpose

13. Type of Immunity Naturally acquired active immunity Naturally acquired passive immunity Artificially acquired active immunity Artificially acquired passive immunity (does not last long) Primary: first exposure (get sick, takes time to make antibodies) Secondary: 2 nd or more exposure (quick response from memory cells)

14. What vaccines have you had? Hepatitis B DPT Polio MMR Hib Pneumococcal