Microbiology Ch 19 – Flashcards
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Which of the following does histamine NOT directly cause? A. smooth muscle contraction B. anaphylactic shock C. increased vascular permeability D. vasodilation
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B. anaphylactic shock
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Which of the following would NOT be an example of a common allergen? A. peanuts B. pollen C. dust mites D. hay fever
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D. hay fever
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A patient enters the emergency room with itchy, swollen hives. This is an example of a ___________ allergic response called __________. A. localized; anaphylaxis B. systemic; urticaria C. localized; asthma D. localized; urticaria
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D. localized; urticaria
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Which of the following is FALSE concerning type II (cytotoxic) hypersensitivity reactions? A. IgM and IgG antibodies bind to antigens on foreign cells. B. Macrophage activity my lead to additional cellular damage. C. IgE binds to mast cells or basophils. D. They are responsible for transfusion reactions.
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C. IgE binds to mast cells or basophils.
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Assuming Rh compatibility is present, which of the following individuals would be able to receive donor blood from any of the four blood types (A, B, AB, and O)? A. O B. B C. A D. AB
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D. AB
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Which type of hypersensitivity is allergic contact dermatitis? A. type IV reaction B. type I reaction C. type III reaction D. type II reaction
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A. type IV reaction
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Which of the following is a characteristic of rheumatoid arthritis? A. Antibodies attach to receptors on thyroid gland cells. B. Immune complexes of IgM, IgG, and complement are involved. C. Antibodies coat acetylcholine receptors at neuromuscular junctions. D. T cytotoxic cells attack joint tissue.
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B. Immune complexes of IgM, IgG, and complement are involved.
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Which of the following is true concerning systemic anaphylaxis? A. Asthma is a type of systemic anaphylaxis. B. Anaphylactic shock results from an increase in blood pressure, which is caused by blood vessel constriction. C. Injected antigens combine with IgE antibodies on the surface of certain cells, causing them to release histamines and other inflammatory mediators. D. Systemic anaphylaxis frequently occurs as a result of exposure to inhaled allergens.
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C. Injected antigens combine with IgE antibodies on the surface of certain cells, causing them to release histamines and other inflammatory mediators.
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Which of the following best describes graft-versus-host disease? A. Immune cells attack transplanted tissue in a privileged site. B. Immune cells in transplanted bone marrow attack the cells of the host. C. The cells of a host reject transplanted bone marrow. D. A tissue transplant is rejected because the host's T cytotoxic cells are activated and kill the transplanted tissue.
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B. Immune cells in transplanted bone marrow attack the cells of the host.
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Which statement regarding cancer immunotherapy is FALSE? A. An immunotoxin is an antigen combined with a toxic agent. B. Monoclonal antibodies are a promising tool for cancer treatment delivery. C. Cancer vaccines may be either therapeutic or prophylactic. D. Cancer immunotherapy is preferable to radiation therapy because it does not involve causing damage to healthy cells.
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A. An immunotoxin is an antigen combined with a toxic agent.
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Which of the following correctly lists the current distribution of HIV infection and AIDS in order of DECREASING prevalence? A. sub-Saharan Africa, Western Europe, Latin America, Australia / New Zealand B. sub-Saharan Africa, Australia / New Zealand, Western Europe, Latin America C. sub-Saharan Africa, Latin America, Western Europe, Australia / New Zealand D. Latin America, sub-Saharan Africa, Western Europe, Australia / New Zealand
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C. sub-Saharan Africa, Latin America, Western Europe, Australia / New Zealand
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Which statement regarding the infectiveness and pathogenicity of HIV is FALSE? A. Attachment of HIV to the target cell depends on the glycoprotein spike (gp120) combining with the CD4+ receptor. B. During latent infections, the provirus directs the synthesis of many new viruses. C. Some cells that do not carry the CD4 molecule can become infected with HIV. D. The ability of the HIV to remain as a provirus shelters it from the immune system.
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B. During latent infections, the provirus directs the synthesis of many new viruses.
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Which of the following is a xenograft? A. the replacement of a human's heart valve with a pig's heart valve B. transplantation of a kidney from a woman to her older brother C. transplantation of a kidney from a woman to her twin sister. D. transplantation of tissue from one area on a person's body to anther
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A. the replacement of a human's heart valve with a pig's heart valve
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When the wasps stung Sally, the injection of venom initiated a type I hypersensitivity reaction called anaphylaxis. Which of the following best describes a hypersensitivity reaction? A. an immune response that results in an overproduction of IgG B. an immune response characterized by an overproduction of T cytotoxic cells C. a hyperactive immune response generated upon initial exposure to antigen D. a reaction that occurs in a sensitized individual resulting in tissue damage rather than immunity
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D. a reaction that occurs in a sensitized individual resulting in tissue damage rather than immunity
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Which of the following mediators are involved in anaphylactic reactions? Select all that apply. - B cells - IgE - mast cells - basophils - IgM - T cells
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- IgE - mast cells - basophils
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The hives that Sally is experiencing are a result of an anaphylactic reaction. This is a multistep reaction resulting from the interaction of the wasp venom and Sally's immune system. Each of the statements below is a step in the anaphylactic response. Arrange the following statements in the order that best represents the chronological order of events in generating an anaphylactic reaction.
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1. IgE molecules bind to mast cells and basophils. 2. Antigen molecules cross-link adjacent IgE molecules. 3. Degranulation occurs. 4. Chemical mediators such as histamine are released. 5. Capillary permeability and smooth muscle contractions increase. 6. Neutrophils and eosinophils move to the site.
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Which of the following is true regarding systemic anaphylactic reactions? Select all that apply. - Systemic reactions are commonly associated with antigens that are ingested or inhaled. - Systemic reactions can result in a dramatic decrease in blood pressure. - Systemic reactions are commonly associated with injected antigens. - A systemic reaction can be fatal in only a few minutes. - Systemic reactions can be treated only with an injection of epinephrine. - Systemic reactions always involve the respiratory system.
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- Systemic reactions can result in a dramatic decrease in blood pressure. - Systemic reactions are commonly associated with injected antigens. - A systemic reaction can be fatal in only a few minutes.
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Predict which of the following outcomes would result from taking an antihistamine. Select all that apply. - decreased contraction of respiratory smooth muscles - decreased stimulation of mast cells - decreased histamine-based stimulation of cells - increased breakdown of the histamine molecule - decreased permeability of blood vessels - decreased mucus secretions
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- decreased histamine-based stimulation of cells - decreased permeability of blood vessels - decreased mucus secretions
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Sally decides to go through the desensitization program recommended by her doctor. What is the overall purpose/goal of this process? A. The process will eliminate all of the wasp venom-specific IgE from Sally's body. B. Repeated exposure to wasp venom antigen will increase the amount of IgG produced by Sally's immune system. C. Desensitization will decrease the overall sensitivity of Sally's immune responses, eliminating its hyperactivity. D. During the desensitization process, the number of wasp venom-reactive mast cells will decrease.
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B. Repeated exposure to wasp venom antigen will increase the amount of IgG produced by Sally's immune system.
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The IgG molecules that are produced during desensitization function as blocking antibodies. These antibodies are extremely effective in providing protection from a hypersensitivity reaction. Why are blocking IgG antibodies so effective at protecting Sally from another anaphylactic response to wasp venom? A. The blocking IgG antibodies "outnumber" the IgE antibodies and bind to wasp venom before the IgE antibodies can bind. B. The IgG molecules bind to the mast cells; but when wasp venom binds, IgG blocks degranulation. C. The IgG molecules bind to mast cells and prevent IgE molecules from binding, thereby preventing degranulation. D. The IgG antibodies bind to the circulating IgE and block their binding to the mast cells.
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A. The blocking IgG antibodies "outnumber" the IgE antibodies and bind to wasp venom before the IgE antibodies can bind.
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(#13)* The level of HIV population in the blood is highest: A. When the patient has clinical AIDS B. When CD4+ levels are the highest C. When the patient is asymptomatic
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C. When the patient is asymptomatic
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The progression from initial HIV infection to AIDS (in the US) usually takes: A. 5 years B. 10 years C. 20 years
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B. 10 years
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Early indication of immune system failure is provided by: A. high levels of HIV virus in the blood B. Seroconversion of HIV C. Falling levels of CD4+ cells
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C. Falling levels of CD4+ cells
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All of the following are true of hypersensitivity EXCEPT A. it is synonymous with "allergy." B. it occurs in the presence of an antigen. C. it occurs when an individual is exposed to an allergen for the first time. D. it is due to an altered immune response. E. it requires previous exposure to an antigen.
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C. it occurs when an individual is exposed to an allergen for the first time.
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The chemical mediators of anaphylaxis are A. found in basophils and mast cells. B. antigen-antibody complexes. C. the proteins of the complement system. D. antigens. E. antibodies.
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A. found in basophils and mast cells.
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Which of the following may result from systemic anaphylaxis? A. hives B. immunodeficiency C. asthma D. hay fever E. shock
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E. shock
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Which antibodies will be in the serum of a person with blood type B, Rh+? A. anti-A, anti-Rh B. anti-A C. anti-A, anti-B, anti-Rh D. anti-B E. anti-B, anti-Rh
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B. anti-A
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Which of the following types of transplant is least compatible? A. isograft B. autograft C. xenotransplant D. allograft E. All of these types of tranplant are equally compatible.
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C. xenotransplant
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Which of the following are used to determine relatedness between a donor and a recipient for transplants? A. HLA antigens. B. ABO blood group antigens. C. MHC antigens. D. HLA and MHC antigens. E. HLA, MHC, and ABO blood group antigens.
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E. HLA, MHC, and ABO blood group antigens.
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Graft-versus-host disease will most likely be a complication of a(n) A. blood transfusion. B. skin graft. C. Rh incompatibility between mother and fetus. D. corneal transplant. E. bone marrow transplant.
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E. bone marrow transplant.
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A positive tuberculin skin test is an example of A. acute contact dermatitis. B. delayed cell-mediated immunity. C. innate immunity. D. autoimmunity. E. psoriasis.
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B. delayed cell-mediated immunity.
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A healthy immune system destroys cancer cells with A. activated macrophages. B. CTLs. C. CTLs and activated macrophages. D. tumor-specific antigens. E. CD+ T cells.
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C. CTLs and activated macrophages.
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The symptoms of an immune complex reaction are due to A. complement fixation. B. destruction of the antigen. C. cytokines. D. phagocytosis. E. antibodies against self.
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A. complement fixation.
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Rheumatoid arthritis is due to deposition of A. complement in joints. B. IgG and IgA complexes in joints. C. IgA antibodies in joints. D. IgD and IgE complexes in joints. E. complexes of IgM and IgG and also complement in joints.
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E. complexes of IgM and IgG and also complement in joints.
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Allergic contact dermatitis is due to A. activated macrophages. B. IgG antibodies. C. IgM antibodies. D. IgE antibodies. E. sensitized T cells.
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E. sensitized T cells.
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Attachment of HIV to the target cell depends on A. CXCR4 binding to the CD4+ receptor. B. gp120 combining with the CD4+ receptor. C. gp120 binding to the CD4+ plasma membrane. D. gp120 combining with the chemokine receptor CCR5. E. gp41 binding to the CD4+ receptor.
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B. gp120 combining with the CD4+ receptor.
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The process of desensitization to prevent allergies involves the injection of increasing amounts of A. antigen. B. antihistamine. C. IgG. D. IgE. E. RhoGAM.
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A. antigen.
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All of the following pertain to serological tests EXCEPT A. they are used to detect compatible tissues for transplantation. B. they can be used to diagnose various diseases. C. reactions can be detected by uptake of trypan blue by damaged cells. D. they can detect antibodies but not antigens. E. they are used to test for specific HLAs on lymphocytes.
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D. they can detect antibodies but not antigens.
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Which of the following statements about type I reactions is FALSE? A. The symptoms occur soon after exposure to an antigen. B. They involve IgE antibodies. C. The symptoms are due to histamine. D. Antibodies bind to mast cells and basophils. E. They involve helper T cells.
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E. They involve helper T cells.
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Which of the following statements about type IV reactions is FALSE? A. Cytokines initiate tissue damage. B. Reactions are primarily due to T cell proliferation. C. Hemolytic disease of the newborn is an example. D. Allergic contact dermatitis is an example. E. Reactions are not apparent for a day or more.
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C. Hemolytic disease of the newborn is an example. ...
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Donor Recipient 1. AB, Rh- AB, Rh+ 2. A, Rh+ A, Rh- 3. A, Rh+ O, Rh+ 4. B, Rh- B, Rh+ 5. B, Rh+ A, Rh+ Which blood transfusions in the table are incompatible? 2 and 5 2, 3, and 5 1 and 2 1, 2, and 3 3 and 4
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2, 3, and 5
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Hemolytic disease of the newborn can result from an A. Rh- mother and an A fetus. B. Rh+ mother with an Rh- fetus. C. AB mother with a B fetus. D. Rh- mother with an Rh+ fetus. E. AB mother with an O fetus.
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D. Rh- mother with an Rh+ fetus.
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All of the following are false regarding Herceptin EXCEPT A. it is used to treat some breast cancer patients. B. it is a vaccine to prevent the development of cancer. C. it neutralizes the growth factor EGF. D. it acts as an immunotoxin to target and kill cancer cells. E. it is an endotoxin that stimulates TNF by macrophages.
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A. it is used to treat some breast cancer patients.
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Which of the following utilizes a combination of monoclonal antitumor antibody and immunotoxin? A. immunologic surveillance B. immunotherapy C. immune complex D. immunologic enhancement E. immunosuppression
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B. immunotherapy
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All of the following are reasons why an HIV vaccination has not been developed EXCEPT A. HIV has a high mutation rate so one vaccination would not be effective to treat the world-wide pandemic. B. use of a weakened virus would potentially transmit the infection. C. there is no known organism that can provide a model of natural immunity. D. vaccines are not effective against viral infections. E. small and inexpensive animals for vaccine research are not available.
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D. vaccines are not effective against viral infections.
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Treatment with certain drugs to reduce transplant rejection can cause A. immunosuppression. B. immunologic enhancement. C. autoimmunity. D. immunologic surveillance. E. immunotherapy.
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A. immunosuppression.
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Which of the following statements about human embryonic stem cells is FALSE? A. They express MHC II antigens. B. They are undifferentiated. C. They express few MHC I antigens. D. They are pluripotent. E. They are typically obtained from the blastocyst stage of embryonic development.
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A. They express MHC II antigens.
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In immune complex reaction shown in the figure, what is the structure labeled "a"? A. complement B. antigen C. mast cell D. antibody E. neutrophil
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B. antigen
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Anaphylaxis is the term for reactions caused when certain antigens combine with A. histamine. B. complement. C. macrophages. D. IgE antibodies. E. IgG antibodies.
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D. IgE antibodies.
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During asymptomatic phase I of HIV disease, HIV infection is diagnosed by A. testing for seroconversion. B. measuring viral RNA. C. measuring antibodies against HIV. D. counting CD4+ T cells. E. counting CD8+ T cells.
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B. measuring viral RNA.
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Chemotherapy to inhibit the progression of HIV infection utilizes all of the following mechanisms EXCEPT A. inhibition of viral proteases. B. termination of viral DNA. C. blockage of viral attachment. D. prohibition of viral integration into host cell DNA. E. destruction of viral ribosomes.
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E. destruction of viral ribosomes.
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Which of the following regions has the greatest distribution of HIV infection and AIDS in the world? South and Southeast Asia Eastern Europe and Central Asia Latin America North America sub-Saharan Africa
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sub-Saharan Africa
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Which of the following is a possible outcome of an HIV infection? A. Infection may initially be asymptomatic. B. There may be persistent yeast infections . C. The disease does not progress to AIDS. D. Virions may remain latent. E. All of the answers are correct.
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E. All of the answers are correct.
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Which of the following is the least likely vaccine against HIV? subunit glycoprotein attenuated virus protein core All of these vaccines are equally likely.
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attenuated virus
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HIV spikes attach to CD4+ receptors found on T helper cells. macrophages. dendritic cells. T helper cells and macrophages. T helper cells, macrophages, and dendritic cells.
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T helper cells, macrophages, and dendritic cells.
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Worldwide, the primary method of transmission of HIV is homosexual intercourse. intravenous drug use. heterosexual intercourse. nosocomial. blood transfusions.
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heterosexual intercourse.
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In immune complex reaction shown in the figure, what is the end result of the reaction? Complement is activated. Antibodies destroy neutrophils. Endothelial cells are damaged. IgG is directed against cell membrane antigens. Neutrophils are attracted and release enzymes.
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Endothelial cells are damaged.
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All of the following regarding "privileged sites" are true EXCEPT A. they explain how animals tolerate pregnancies without rejecting the fetus. B. they include corneal and brain tissue. C. they do not have lymphatic vessels. D. they include any tissue transplanted from a pig. E. they are rarely rejected.
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D. they include any tissue transplanted from a pig.
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All of the following are considered examples of type I hypersensitivity EXCEPT penicillin allergic reactions. transplant rejections. pollen allergies. asthma. dust allergies.
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transplant rejections.
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All of the following lead to drug-induced thrombocytopenic purpura. Which occurs first? Antibodies and complement react with platelets. Antibodies against haptens are formed. Drug binds to platelets. Purpura occurs on the skin. Platelets are destroyed.
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Drug binds to platelets.
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Immunodeficiencies are a result of all of the following EXCEPT cyclosporine. DiGeorge syndrome. autoimmune diseases. HIV infection. Hodgkin's disease.
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autoimmune diseases.
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Which of the following describes a cytotoxic autoimmune reaction? Mediate by T cells. Antibodies are not made. Antibodies react to cell-surface antigens. Cells are killed. Immune complexes form.
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Antibodies react to cell-surface antigens.
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Symptoms of delayed cell-mediated reactions are due to neutrophils. cytokines. IgG antibodies. IgE antibodies. antigens.
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cytokines.
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Which type of response does the process of desensitization produce? IgE IgM T-cell IgG
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IgG
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The initial symptom of HIV infection is A. appearance of thrush. B. loss of T cells. C. lymphadenopathy D. significant weight loss E. high viral load.
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C. lymphadenopathy
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The number of T cells drops to below 200 cells/microliter in which phase of HIV infection? phase 1 phase 2 initial phase asymptomatic phase phase 3
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phase 3
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In rheumatoid arthritis, IgM, IgG, and complement deposit in joints. This is an example of A. acquired immunodeficiency. B. cell-mediated autoimmunity. C. immune complex autoimmunity. D. cytotoxic autoimmunity. E. immunosuppression.
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C. immune complex autoimmunity.
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The following events occur if human cells expressing HLA-I are mixed with anti-HLA-I, complement, and trypan blue. What step indicates the cells are HLA-I? A. Trypan blue enters the cells. B. Enzyme is released from neutrophils. C. Cells are damaged by complement. D. Anti-HLA antibodies bind to HLAs on lymphocytes. E. None of the answers are correct; the T cells are missing.
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A. Trypan blue enters the cells.
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Vaccines against HIV have proven to be very effective in halting the spread of disease. True False
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False
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All hypersensitivities involve antibody-antigen reactions. True False
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False
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Skin tests are reliable indicators for the diagnosis of food-related allergies. True False
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False
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Xenotransplantation is an effective alternative to using isografts. True False
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False
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All stem cells are derived from embryonic stem cells. True False
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False
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Cancer is similar to an infectious disease in that it is due to a failure of the bodys defenses. True False
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True
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Individuals who do not express CCR5 are highly resistant to infection by HIV. True False
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True
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HIV attack of CD4+ T cells causes suppression of both cell-mediated and humoral immune responses. True False
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True
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Autoimmune diseases occur when the immune system is unable to discriminate self from nonself." True False
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True
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HIV is a retrovirus with single-stranded RNA. True False
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True
