Chapter 40

1. Chapter 40 The Immune System

2. immune system pathogens *The ____________________ is the body’s main defense against _________________. - Pathogens = __________________________. ______________ = To fight _____________through the production of _______that inactivate foreign substances or other cells. *** There are _________types of defense mechanisms that fight infection: ________________ _______________ and _____________________. A disease causing agent Function infection cells two nonspecific defenses specific defenses

3. physical chemical • Nonspecific Defenses (includes both _______________ and __________________ barriers) A. First Defenses 1. Keeping pathogens _________. a. includes ________________________________________ _____. b. The __________ is the most important and it keeps _____ pathogens out! c. ________________ can kill many different types of ______________. out skin, mucus sweat and tears skin most secretions bacteria

4. SKIN

5. Mucus, saliva, and tears lysozymes cell walls 1) _____________________ contain __________ which can kill the ____________. 2) ________and ___________ make an _____________ environment that kills bacteria. 3) Openings like the mouth and nose are protected by _________ and _____________________. Oil sweat glands acidic mucus ciliated cells

6. B. Second Line of Defense 1. What happens when the pathogens enter your body and multiply? a. The _________________________ is activated = a_________________________reaction to ___________________ caused by injury or ________________. 1) When a ___________ is detected, the immune system makes millions of __________________________ (they fight infection!). inflammatory response nonspecific defense tissue damage infection pathogen white blood cells

7. Red blood cells Platelets White blood cell (T-Cell)

8. swelling, redness, and pain expand 2) The blood vessels near the wound _________ and to move the cell into the infected area. 3) Many of the white blood cells are _____________ that __________ the pathogens. 4) This response causes ___________________________. phagocytes engulf

9. raise core temperature b. The immune system can also ________ the ________________________ of the body when it is necessary. 1) __________ = A raise in the body’s core temperature in response to __________. 2) The temperature increase can kill many sensitive pathogens that can only ________________ at ___________________________. 3) An increase in temperature also ____________________________ which moves the white blood cells through the body ___________. Fever infection survive specific temperatures speeds up the heart rate faster

10. C. Interferon 1. Some cells that are infected with a virus makes a group of ________________called___________. a. Interferon __________ the virus’s ability to make proteins and reproduce. proteins interferon slows

11. nonspecific defense II. Specific Defenses A. If a pathogen can get past the_____________________________ the immune system will attack a _____________ type of pathogen through an __________________. B. The _____________ that triggers the immune response is called an ______________. (ex. Viruses, bacteria, etc.) specific immune response substance antigen

12. two lymphocytes 1. Antigens are recognized by ________ types of _______________________. a) _________________ (B cells) - Provide immunity against antigens and pathogens in the ____________. - This is called ___________________. B- lymphocytes body fluids humoral immunity

13. T Lymphocytes b) ______________ (T cells) - Defend against ________________ and pathogens inside living cells. - This is ______________ __________. abnormal cells cell-mediated immunity

14. multiply C. Humoral Immunity 1. B cells recognize a pathogen and then __________ rapidly, making ___________________ and __________________. a) Plasma cells release ___________ = proteins that recognize and bind to antigens. plasma cells memory B cells antibodies

15. antibodies bloodstream 2.The _______________ travel in the ___________________ to get to the foreign pathogens where they overwhelm them. 3.The plasma cells die out and ________ producing the antibodies as the infection is overcome. a) Millions of ______________________ cells are left over and are able to produce the __________________. b) If the __________ antigen enters the body again, a _________________ is triggered and the memory B cells ____________ to make new _______________________ with same antibodies. stop memory B cells same antibodies same secondary response divide new plasma cells

16. PRIMARY RESPONSE (initial encounter with antigen) Antigen Antigen receptoron a B cell Antigen binding to a B cell Cell growth, division, and differentiation Clone ofcells Memory B cell Plasma cell Antibody molecules Later exposure to same antigen SECONDARY RESPONSE (can be years later) Cell growth, division, and further differentiation Larger clone of cells Plasma cell Memory B cell Antibody molecules Figure 24.9

17. Primary and Secondary Response Curves

18. Antigen-binding sites “Y” D. Antibody Structure 1. Antibodies are shaped like a _____. 2. ____ identical binding sites for antigens. 3. Like an _____________, the _____________ of the binding site determines which antigens it can bind with. 2 enzyme shape

19. Antigen molecules Variety ofB cells in a lymph node Antigen receptor(antibody oncell surface) Cell growth division, and differentiation Clone of manyeffector cellssecretingantibodies Endoplasmicreticulum Antibodymolecules Figure 24.7

21. types millions a) Because there are so many different _______ of antigens, our bodies must make ________________ of different types of ____________________. E. Cell-Mediated Immunity 1. Cell Mediated Immunity = The body’s defense against it’s ________________ when they turn ___________ the body (i.e. cancerous cells, virus-infected cells, fungi, protists). 2. Antibodies __________________ destroy them. antibodies own cells against cannot alone

22. differentiate Killer T Cells • T-cells divide and _________________ (become specialized in structure and function) a) ____________________ - Locate and ___________________ bacteria, fungi, or foreign tissue that has the ____________. b) _____________________ - Activate _______ T cells to divide and also stimulate B cells to ______________. - They make ___________________. destroy antigen Helper T Cells Killer differentiate memory T Cells

23. Microbe Macrophage Antigen from microbe(nonself molecule) Self protein Self protein displaying antigen T cell receptor Bindingsite for self protein Helper T cell Binding site for antigen Helper T Cells Figure 24.13A

24. Suppressor T Cells Holeforming Foreignantigen INFECTED CELL CytotoxicT cell slows the development killer T Cells c) __________________________ - Releases a substance that ___________________________ or shuts down the _______________ when the __________ is under control. d) _________________________ - Will cause a _________________________ if the same antigen appears again. infection Memory T Cells secondary response

27. organ acceptance F. Transplants 1. Killer T cells can make _____________________ difficult. 2. Body cells have _____________________ on their surface that the recipient’s ____________ do not recognize. marker proteins T cells

28. attack rejection a) The immune system begins to ________________ the transplanted organ in a process called ___________________. b) This is why it is important for __________ to have many of the same cell markers as the __________________. c) Recipients must take drugs that _____________ cell-mediated immunity. donors recipient suppress

29. Active Immunity III. Acquired Immunity A. Active Immunity 1. _________________________ = Immunity produced from a vaccine. 2. Vaccination = The injection of a ___________________________ in order to produce ____________________. weakend pathogen immunity

30. 20 prevented a) More than _____ different human diseases can be _________________ by vaccination. b) Modern vaccines ____________ the immune system to create millions of different _______________________. 3. Active immunity can result from _________________ or from _____________. stimulate plasma cells natural exposure vaccines

31. Passive immunity another animal B. Passive Immunity • ___________________ = Antibodies from ____________________ are injected into the bloodstream. 2. Passive immunity is __________________ because the body’s immune system will ______________ the foreign antibodies. 3. Passive immunity can also occur __________________ or ________________. Ex.- Antibodies produced by a pregnant mother can be passed through the placenta (or through breast milk) to the fetus. This protects an infant inthe first few month’s of it’s life. temporary attack naturally intentionally

33. AIDS (Acquired Immune Deficiency Syndrome) viral • AIDS is a ___________ infection. - AIDS destroys_______ __________. - The cause of AIDS is _______ (Human Immunodeficiency Virus) Helper T cells HIV

34. How HIV works Helper T Cells retrovirus • HIV targets ______________ 1. HIV is a _______________ = a virus that carries it’s information in the form of _____. 2. When a HIV virus attaches to a helper T Cell, it injects it’s RNA which uses a process called ______________________. a. The ____________ forces the cell’s DNA to make copies of itself. Some become part of the original cell’s ______ while others stay in the cytoplasm. RNA reverse transcriptase Viral RNA DNA

36. Viral DNA virus 3. When the ______________ is activated, the host cell begins to make the parts of the ________. a. These parts are assembled and then __________ the cell to infect other cells. leave Virus emerging from a T cell.

37. inside antibodies T cells B. They grow ________ T-cells therefore they are not affected by ____________. 1. Over time _________ are destroyed which lowers ____________ and _____________ immunity. a. The fewer number of __________ means that the body is more susceptible to other __________. 2. A person is diagnosed with AIDS when their T cell count goes below ________. humoral cell-mediated T cells diseases 200/mm3