1. The Immune System

2. Disease Transmission Robert Koch…”father of disease,” came up with first procedure for identifying the pathogens responsible for a disease. -Worked with anthrax -Koch’s Postulates – “rules” for determining the cause of the disease

3. Human Diseases and How They Are Transmitted AIDSHIVIntercourse, contaminated syringes Common Coldmany virusesair, person to person Malariaprotozoan parasitesmosquitoes Measlesparamyxovirusair, person to person BotulismClostridium botulinumcontaminated food

4. Invaders to the Body  Pathogens – foreign particles Ex. Viruses + bacteria Ex. Viruses + bacteria  Multiply in the body to cause infection  Come into contact with the body by: Air Air Food Food Water Water Person-to-person contact Person-to-person contact Animal bites Animal bites

5. NonSpecific Defenses...First Line of Defense Skin – prevents entry Skin – prevents entry Oil – traps and kills invaders Oil – traps and kills invaders Mucous/tears/saliva – wash, trap, and kill Mucous/tears/saliva – wash, trap, and kill Mucous/saliva – swallowed; stomach acid killsMucous/saliva – swallowed; stomach acid kills Ear wax – traps Ear wax – traps Hair/Cilia - traps Hair/Cilia - traps

6. NonSpecific Defenses...Second Line of Defense If a pathogen penetrates the first line of defense... 1. Inflammatory Response: -Histamine released (Increases blood flow to site of injury/infection; can cause redness, swelling, warmth, and pain) - White Blood Cells (Phagocytes) Attack/ingest foreign particlesAttack/ingest foreign particles Neutrophils & MacrophagesNeutrophils & Macrophages Natural Killer CellsNatural Killer Cells

7. 2. Interferon protein that inhibits reproduction of virusesprotein that inhibits reproduction of viruses 3. Fever sign body is responding to infectionsign body is responding to infection suppresses growth and reproductionsuppresses growth and reproduction promotes action of white blood cellspromotes action of white blood cells

8. Specific Defenses...The Immune System 1. Bone Marrow -Produces white blood cells (lymphocytes) -Two types: B cells & T cells (thymus) 2. Thymus -Place of maturation of white blood cells 3. Lymph & Lymph Nodes -Filter pathogens, lymphocytes 4. Spleen -Filters pathogens from blood

9. 5. Tonsils & Adenoids -Contain lymphocytes which are important for antibody production.

10. The Immune Response..two pronged attack! Begins with ‘Recognition’ of an Antigen (pathogen). -differing response based upon surface proteins on the antigen. 1. Cell-Mediated 2. Humoral

11. 1. Cell-Mediated Immune Response -T cells (cytotoxic & suppressor) -destroy infected cells -shut down response after pathogens are cleared 2. Humoral Immune Response -B cells change into plasma cells and produce antibodies. Antibodies – chemicals that binds to antigen to disable the pathogen (block reproduction). -Antigen specific -Stores antibodies for the future use

12. Primary Immune Response -first time the body encounters an antigen. Secondary Immune Response -Response of memory cells to an infection by a former pathogen.

13. Additional Specific Defenses  Immunity (survival or vaccination)  Allergies  Autoimmune Diseases- immune system attacks your own body cells. (MS, type I diabetes, rheumatoid arthritis) type I diabetes, rheumatoid arthritis)

14. AIDS AIDS is a disease in which the immune system loses its ability to fight off pathogens and cancers. Caused by the HIV virus Transmitted by the transfer of body fluids & needles.