2. Topic: Disease: How does our body come under attack?

3. 1. What is a disease? Disease is any condition that prevents the body from working as it should. As a result the body may fail to maintain homeostasis.

4. 2. What can cause disease? Disease in humans may result from foreign invader organisms called….. PATHOGENS

5. 3. Pathogens Bacteria Viruses Fungi Parasites

6. Bacteria Characteristics Called Prokaryotes One-celled organisms Lack most ORGANELLES, no true nucleus.

7. Examples Strep throat Salmonella – toxins Syphilis What will the doctor Give you? Antibiotics The salmonella bacteria give off a toxin that causes you to get sick.

8. Bacteria and antibiotics

9. Virus A VIRUS IS NOT A CELL (IT IS NOT ALIVE) DNA or RNA + Protein Coat Very small, smaller then a CELL. They can only reproduce INSIDE a cell. A virus works by injecting its DNA into a cell, turning the cell into a virus producing factory.

10. Examples HIV Chicken Pox Influenza Can you take antibiotics?

11. Fungus Athlete’s foot Ring worm What can the doctor Prescribe? Fungicides

12. Parasites Some animals and one-celled organisms survive by living and feeding on other organisms.

13. 4. How are pathogens transmitted? Blood Food Sex Air Animal

14. 5. Diagnosing – determine the disease you have Diagnosis is made based on symptoms and an examination

15. 6. Prevention vs. Treatment Prevention – ways to avoid getting the disease. (wash hands, exercise, diet plans etc.) Treatment – ways to help people with a disease to get better. (medicine, surgery, diet plans, etc.)

16. 7 Besides pathogens, what else can cause disease? Organ Malfunction Toxic Substances Inherited Disorder Risky Personal Behavior Poor Nutrition

17. Topic Immune System: Structures and Functions: How does our body defend us from pathogens?

18. 1. Pathogens Any disease-producing agent especially a virus, bacterium, fungus, or parasite.nydiseaseproducing agentespeciallyavirus bacterium

19. 2. 1 st Line of Defense Skin Mucus Tears in eyes Acid in stomach There are often enzymes in these substances that are able to destroy pathogens (tears & sweat). Others like the stomach provide acidic environments that are inhospitable to most pathogens. Hair and mucus serve to trap potential disease causing pathogens.

20. 3. 2 nd Line of Defense The Immune System

21. Cellular Components: 4. White Blood cells Large cells with a nucleus. Less numerous than RBC’s. Defenders of the body. Types: Phagocytes: engulf and destroy bacteria (Macrophages) Lymphocytes: produce antibodies (B-Cells)

22. 5. Immune System Made of proteins, cells, and tissues that identify and defend the body against foreign chemicals and organisms

23. 6. How does our immune system identify foreign cells? A protein on the cell The ID tag identifies the invader as not belonging to the body (non-self). This ID tag is called an antigen. All cells have recognition proteins!! Antigen Recognition proteins on our cells (self) are not targeted by our immune system.

24. 7. Phagocytes – Engulf the Pathogens Phagocytes: White blood Cells that Eat a pathogen

25. 8. Lymphocytes – Produce antibodies They can make antibodies, which are their weapons against the foreign antigens. Antibodies & Antigens are both proteins!!

26. 9. Antibodies They are “Y” shaped proteins, made by __________ They are weapons that fight against pathogens Pathogen Antigens Antibodies B-Cells

27. How are nuts and screws similar to antigens and antibodies? Antibodies are made specifically to match the shape of the antigen. 1 antigen = 1 antibody What does this remind you of?

28. 11. How do antibodies destroy pathogens? When the antibody attaches to the antigen, it breaks open its cell membrane Or, the antibody attaches to the antigen, and a phagocyte will know to engulf it

29. 12. Our Immune System has a good memory! The first response is relatively slow and weak because time is needed for enough WBCs to form and defeat the pathogen. The second response to the same pathogen triggers a quicker and stronger response. ** After the first response, the immune system “remembers” specific pathogens by leaving behind WBCs that protect the body for years (memory cells).

30. Topic: Vaccines: How does your body become immune (resistant) to disease?

31. Bioterrorism Fatal hemorrhagic smallpox in a twelve-year-old girl, 1970s, Bangladesh. A genetically - engineered strain of smallpox might produce unusual symptoms such as these. Here, the eyes are filled with blood, and blood blisters form in the mouth and inside the body. How can we protect ourselves? vaccines Today there is mounting concern about the threat of a bioterrorist attack using smallpox -- so much concern that in October 2001 the American government decided to order enough vaccines to protect every U.S. citizen. Smallpox has a fearsome reputation, having killed more people in history than any other infectious disease.

32. 1. What is a vaccine? A vaccine is a dose of a pathogen or part of a pathogen that has been disabled or destroyed so it is no longer harmful, but it still has the antigens present. Weakened Pathogen Antigen Antibody These antigens trigger an immune response.

33. How was the first Vaccine developed? English physician Edward Jenner developed an inoculation against smallpox in 1796. Armed with the knowledge that milkmaids who had been exposed to cowpox, a relatively mild affliction, didn't come down with smallpox, Jenner intentionally infected an eight-year-old boy with cowpox. Two months later he infected the boy again, this time with smallpox. As Jenner expected, the child didn't come down with the disease -- he was immune.

34. Vaccines depend on the “memory” of the immune system. The first response is relatively slow and weak because time is needed for enough WBCs to form and defeat the pathogen. The second response to the same pathogen triggers a quicker and stronger response. ** After the first response, the immune system “remembers” specific pathogens by leaving behind WBCs that protect the body for years (memory cells).

35. 2. How do scientists make vaccines? http://www.pbs.org/wgbh/nova/bioterror/va ccines.html http://www.pbs.org/wgbh/nova/bioterror/va ccines.html 1)Obtain pathogen 2)Treat pathogen to kill or weaken it. 3)Inject altered pathogen (vaccine) into organism. 4)Body responds to antigens by making antibodies & having WBCs attack invader. 5) Some WBCs specific for this pathogen remain in the body to protect the organism from future attacks.

36. 3. What happens when you get invaded by the real pathogen? Some white blood cells specific for this pathogen (called Memory Cells) are already present and will multiply quickly and destroy the invader before it has the chance to cause the disease. Memory Cells

37. 4. What is immunity? The ability of a person who once had a disease to be protected from getting the same disease again. She was very ugly! The ugliest one in our community. She went to the beauty parlor so often She built up an immunity.

38. 5. Immune response Antibody Concentration Time First exposure Second exposure Interval between exposures Vaccine Real Pathogen

39. 6. Active vs. Passive immunity Active Immunity You make your own antibodies to fight the pathogen Long lasting Passive Immunity You get antibodies from a different organism, you don’t make your own antibodies Short lasting

40. How are these two types of immunity different?

41. Topic: How does HIV affect the immune system?

42. What could have made him look so sick?

43. 1. How can we contract HIV? Sexual intercourse Blood transfusion Passed through the placenta Open wound Sharing needles - drugs

44. 2. What is HIV? It is a virus that attacks our immune system. It is a retrovirus. It has RNA not DNA as its genetic material. How does our body know this is an enemy? ANTIGEN

45. 3. What part of our immune system does it attack? White blood cells HIV attacks special WBC’s called T-Cells

46. 4. How are B-cells different than T-cells? Make antibodies Send signals to B-cells to make antibodies

47. 5. How does HIV replicate? HIV binds to a T-cell It inserts its RNA into the T-cell It produces HIV DNA It hides HIV DNA inside the cell's DNA: This turns the cell into a HIV factory. HIV Virus T-Cell

48. 6. Effects You don’t die from the HIV infection, rather you die from the diseases/infections you get because your body can’t defend itself. (ex: pneumonia) These infections are called OPPORTUNISTIC INFECTIONS.

49. Can we make a vaccine? It is very difficult because the virus mutates very quickly and produces different antigens after only a few generations.

50. Where is AIDS an epidemic?

51. Topic: How can the immune system malfunction?

52. 1. How can your immune system malfunction? 1.Allergies 2.Asthma 3.Autoimmune Disease 4.Organ Transplants

53. 2. What is an allergy? An allergy is a rapid immune system reaction to environmental substances that are normally harmless. Can you think of materials that can cause allergic reactions?

54. 3. What are things that cause allergies? HOUSE DUST BEE POLLEN MOLD RAGWEED Allergens

55. 4. Allergic reactions Inflammatory response: allergen attaches to mast cells which release histamines. Histamines are chemical that call trigger an inflammatory response (capillaries swell) Hives, nausea, or shock What can we take for allergies?

56. 5. Asthma is an allergic reaction Allergic reaction that causes your respiratory ducts to swell up

57. 6. Autoimmune disease The word "auto" is the Greek word for self. If a person has an autoimmune disease, the immune system mistakenly attacks self, targeting the cells, tissues, and organs of a person's own body. The immune System fails in distinguishing between self and non-self.

58. 7. Examples of Autoimmune diseases Diabetes is a disease, which prevents the body from properly using food energy. In MS, the immune system attacks the protective coating around nerves, called myelin.

59. Rheumatoid arthritis Joints swell

60. 8. Why are organ transplants difficult? This is a kidney being removed from a donor The donor will have his own ID tags on the cell membrane. What are these ID tags called?

61. 9. How will the recipient react? A transplanted organ is recognized as foreign and is attacked by the immune system (REJECTION). The chance of REJECTION is less when the donor and recipient are closely related or when anti-rejection medication is used.

62. 10. Why take an immunosuppressant? It will suppress your immune system and reduce the chance of destroying the transplanted organ. What is the risk of suppressing the immune system? It increases the patient’s risk for an infection.