1. Chapter 40

2.  Helps protect body from disease  Collects fluid lost from blood vessels and returns fluid to circulatory system

3.  White Blood Cells  Thymus  Spleen  Lymph Nodes  Lymph Vessles  Bone marrow  Blood vessels

5.  Disease – Any change, other than injury, that disrupts the normal function of the body ◦ Pathogens – disease causing agents

6.  Germ Theory of Disease –diseases are caused by microorganisms called germs ◦ How do we know what causes a disease? Ex. Lyme disease

9.  Koch’s Postulates ◦ Developed by Koch ◦ Series of rules used to identify the microorganism that causes a disease ◦ Identification is the first step to a cure

10.  Koch’s Postulates (page 1032) ◦ Pathogen should be found in body of a sick organism and not in a healthy ◦ The pathogen must be isolated and grown in lab in pure cultures ◦ The cultured pathogens, when placed in a new host, should cause same disease as the original host ◦ When isolated from the second host, it should be identical to original pathogen

11.  Agents of Disease ◦ Pathogens cause disease by  Destroying cells  Releasing toxins  Disrupting bodily functions  Remove nutrients  Block blood flow

12. ◦ Viruses  Tiny particles  Invade cells and replicate  Attach to cell and insert genetic information  Common cold, influenza, smallpox, and warts Chicken Pox

13. Human papilloma virus

14. ◦ Bacteria  Cause of disease  Breaking down tissues  Releasing toxins  Streptococcus, diphtheria, botulism, and anthrax

16. ◦ Protists  Malaria - mosquitoes  Trypansoma – contaminated blood  Amebic Dysentery – contaminated water Malaria

17. ◦ Worms  Tapeworms and hookworms ◦ Fungi  Athlete’s foot  Ringworm Wuchereria bancrofti (worm)

18.  Spreading Disease ◦ Direct/Indirect Contact ◦ Contaminated food and water  Food poisoning ◦ Infected Animals  Vectors – animals that carry pathogens

19.  Fighting Infectious Diseases ◦ Antibiotics – compounds that kill bacteria  Penicillin – 1928 Alexander Fleming

20.  Fight infection by making cells that inactivate foreign substances or cells which we call immunity

21.  1. Nonspecific Defenses ◦ Physical Barriers ◦ Chemical Barriers

22. ◦ First line of defense – Keeps pathogens out of the body  Skin – most important nonspecific defense  Mucus, sweat, and tears – contain lysozyme  Lysozyme – enzyme that breaks down the bacteria’s cell wall

23. ◦ Second line of defense  Inflammatory response – Reaction to tissue damage caused by injury or infection  WBC or phagocytes kill bacteria  Fever – Increased body temperature  Slows or stops bacteria growth  Increases heart rate

24. ◦ Interferon – a group of proteins that help healthy cells resist viral infection

25.  Immune response – Specific defenses that attack pathogen  Antigen – Substance from virus/ pathogen that triggers the response  T cells – T Lymphocytes  B cells – B Lymphocytes

26.  Humoral Immunity – Response to antigens and pathogens in body fluids  B Cells – Identify antigen and quickly multiply  Plasma cells – release antibodies  Antibodies – proteins that recognize and bind to antigens  Memory B cells

27. ◦ Antibody Structure  Y shaped amino acid  Two identical binding sites  100 million different antibodies

28. ◦ Cell-Mediated Immunity – Response to abnormal cells and pathogens inside living cells  T cells – divide during infection or cancer  Killer T cells – kill pathogen  Helper T cells – make memory T cells  Suppressor T cells – Shutdown killer T cells  Memory T cells

29.  Body attacks foreign organs  Recipients must take drugs to resist rejection

30.  1. Acquired Immunity ◦ Edward Jenner developed the first vaccine  Smallpox

31.  2. Active Immunity  Vaccination – injection of weakened or mild form of virus  Long time response

32.  3. Passive Immunity – Exposure to antibodies of an animal that has had an infection  Colostrum from mother’s milk  Shorter time protection

33.  Allergies – An overreaction to antigens on mast cells ◦ Allergens - Pollen, dust, mold, and bee sting ◦ Histamines – Chemicals released by mast cells that cause inflammation

34.  Asthma – Chronic respiratory disease ◦ Causes - Infection, exercise, stress, medication, cold air, pollen, dust, tobacco smoke, pollution, molds, and pet dander

35.  Autoimmune Diseases – Immune system attacks it’s own cells ◦ Type I Diabetes ◦ Rheumatoid arthritis ◦ Myasthenia gravis ◦ Multiple sclerosis

38.  AIDS – Acquired immunodeficiency syndrome ◦ Viral infection that attacks helper T cells ◦ Immune system breaks down

39. ◦ HIV – Human immunodeficiency virus  Retrovirus  Destroys helper T cells  Forces the human cells to make more HIV

40. ◦ Transmission  Sexual contact  Shared needles  Contact with blood  Mother to child

41.  Maintaining Health ◦ Healthy Diet ◦ Exercise and Rest ◦ Abstaining from Harmful Activities ◦ Regular Checkups