Microbiology 33 Final Lecture Exam A & B (GRADED A) Questions and Answers

El Camino College Compton Educational Center Microbiology 33 Final Lecture Exam A & B By Dr. Eyob Wallano Instruction: Please use the provided scantron to answer all questions from each section. 5% will be taken off from your total score if any marking is left on the exam booklet. Section E and F will be answered separately on provided paper and submitted with the booklet. Section A. Multiple Choice 1. An epidemic disease is one that A. breaks out in higher than usual proportions in a population. 2. A scientist who studies the patterns of disease in a community and attempts to locate its source is called a(n) B. epidemiologist. 3. What specific job is this person fulfilling? She isolates the cause of an outbreak, prevents its spread, and gets out public health messages to people who could have been exposed. C. Epidemiologist 4. The relationship between the human body and its microbiota D. is an example of a symbiosis. 5. Which of the following would be the reservoir of infection for a zoonosis? D. Animal 6. Which of the following is an example of indigenous microbiota? Indigenous microflora is defined as the community of micro-organisms that live on or in another living organism or in a particular environment. These micro- organisms include bacteria, algae and fungi. A. Escherichia coli in the intestines B. Candida albicans in the intestines C. Lactobacillus in the human vagina D. All of the above are correct 7. Indigenous microbiota may be found in all of the following environments except A. the blood. 8. Which one of the following does not contribute to the virulence of a bacterial species? D. Its ability to grow on artificial laboratory media. 9. Certain microorganisms inhabit parts of the body without causing symptoms of disease. These organisms collectively are referred to as A. indigenous microbiota. 10. The degree to which an organism is able to cause disease is referred to as its B. pathogenicity 11. Pathogenicity islands refer to B. clusters of genes responsible for virulence. 12. Opportunistic organisms are those that C. are usually commensals but can cause disease when body defenses are suppressed. 13. The organisms that infect individuals with AIDS D. are examples of opportunistic organisms 14. Pseudomonas aeruginosa is a soil organism. Every time we eat a fresh salad, we consume millions of these organisms. They usually do us no harm. However, these same organisms can cause serious infection in persons who have been severely burned. Such a pathogen is called C. opportunistic. 15. Pneumocystis pneumonia in an AIDS patient would be considered a(n) D. secondary disease. 16. Such factors as the number of organisms, their generation time and virulence, and the level of host resistance can influence B. the incubation period for a disease. 17. Chronic diseases are those that A. develop rapidly and come to a climax. B. linger for long periods of time. C. occur in epidemic proportions. D. are subclinical. 18. In the prodromal phase of a disease, signs and symptoms A. are at their most severe. B. may include nausea, fever, and headache. C. have begun to disappear. D. have not developed yet and there is no sign of disease. 19. A disease that develops rapidly, shows substantial signs and symptoms, comes to a climax, and then fades, is a(n) A. acute disease. B. prodromal disease. C. systemic disease. D. chronic disease. 20. The period of a disease during which the symptoms subside is often referred to as the A. period of decline. B. period of convalescence. C. prodromal phase. D. climax. 21. Tetanus will not occur in the tissue of the small intestine because A. the organisms will grow, but do not produce toxins in this area. B. the body's white blood cells are particularly active. C. lymph does not flow through the intestine. D. the portal of entry for the tetanus spores was incorrect. 22. Adhesins may be associated with all of the following bacterial structures except A. pili. B. flagella. C. capsules. D. cilia. 23. Invasiveness refers to the ability of a parasite to A. enter through a variety of portals of entry. B. add to its virulence by transduction. C. penetrate tissues and cause structural damage. D. convert toxins to toxoids. 24. The organisms that cause botulism and tetanus both cause disease by the production of A. spores. B. coagulase. C. exotoxins. D. anaerobic growth. 25. An important effect of hemolysins is A. destruction of phagocytes in the blood. B. endotoxin shock. C. release of iron that the pathogen needs for its metabolism. D. lysis of neutrophils and lymphocytes. 26. Which one of the following does not apply to endotoxins? A. They are composed exclusively of protein. B. They are part of the bacterial cell wall. C. They are present in gram-negative bacteria. D. Endotoxins do not stimulate an immune response that leads to the production of antibodies. 27. Hyaluronidase is a bacterial enzyme that A. induces blood clot formation in the host. B. encourages movement in the organism. C. enhances penetration through the host tissues. D. destroys blood clots. 28. Leukocidin is a bacterial enzyme that can A. enhance tissue penetration. B. destroy phagocytes. C. destroy blood clots. D. clot blood. 29. The ability of the body to restrict the spread of a bacterial infection might be overcome if A. exotoxins are produced by the organism. B. the portal of entry of infectious organisms is incorrect. C. the organism produces streptokinase. D. hemolysin is liberated in the environment. 30. Endotoxin shock may follow A. removal of the acetylcholine from the synapse. B. interruption of the metabolism of gram-positive bacteria. C. injection of antitoxins to the body. D. antibiotic treatment of a disease due to gram-negative bacteria. 31. When the body has been exposed to exotoxins A. it will respond with toxoids. B. it will develop endotoxin shock. C. it will produce antitoxins. D. it will start to form clots. 32. A microbial poison produced during the metabolism of a bacterium and immediately released into the environment is a(n) A. antitoxin. B. exotoxin. C. endotoxin. D. toxoid. 33. If a pathogen is part of a biofilm, its virulence is enhanced because A. it can produce more toxins. B. it is protected from phagocytes and drugs. C. its infectious dose is decreased. D. it is more invasive. 34. Endotoxins are produced by A. fungi. B. gram positive bacteria. C. gram negative bacteria. D. viruses. 35. Changes in the permeability of the blood vessels often accompany diseases caused by gram negative bacteria. This permits leakage of blood fluid to the intercellular spaces, and the patient may lapse into a coma. This condition is referred to as shock. A. endotoxin B. exotoxin C. toxoid D. antitoxin 36. All of the following are characteristics of endotoxins except A. usual source is gram negative bacteria. B. a product of the LPS complex. C. cannot be converted to toxoid. D. can elicit antibody production. 37. The enzyme produced by virulent staphylococci that catalyzes the formation of a blood clot which gives them protection against phagocytosis is A. streptokinase. B. coagulase. C. hyaluronidase. D. hemolysin. 38. Which one of the following is not a direct method by which diseases can be transmitted? A. Touching an animal B. Inhalation of articles of mucus expelled from the respiratory tract C. Hand-shaking D. Fomites 39. Which of the following is an example of vehicle transmission? A. Gonorrhea acquired through sexual intercourse with an infected person B. A cold acquired through inhalation of respiratory droplets C. Salmonellosis acquired through ingestion of contaminated food D. Malaria acquired through the bite of a mosquito 40. A person who harbors a pathogen and is a source of infection to the next person is best referred to as a(n) A. acute source. B. chronic source. C. subclinical source. D. carrier. 41. A disease that is usually present at a low level in a certain geographic area is said to be A. epidemic. B. pandemic. C. endemic. D. ubiquitous. 42. A disease that is found in high numbers world wide such as HIV/AIDS is said to be A. epidemic. B. pandemic. C. endemic. D. ubiquitous. 43. An abnormally high number of measles cases in one American city would be classified as a(an) A. epidemic. B. pandemic. C. endemic. D. outbreak. #44. Nosocomial infections account for an estimated 2 million infections and 90,000 deaths each year in the United States. Which of the following is not a common cause? A. Inefficient air handling mechanisms B. A high prevalence of pathogens in a hospital C. A high number of patients who represent compromised hosts and susceptible to pathogens D. Efficient mechanisms of transmission from patient to patient 45. Which of the following scientists was an early pioneer in immunology with the first vaccination against smallpox? A. Metchnikoff B. Jenner C. Pasteur D. Yersin 46. Which early scientist proposed the theory of phagocytosis, where human white blood cells could capture and destroy disease causing microbes inside the body? A. Metchnikoff B. Jenner C. Pasteur D. Yersin 47. Which early scientist developed vaccines for chicken cholera and rabies? A. Metchnikoff B. Jenner C. Pasteur D. Yersin 48. Which of the following is the best definition for innate immunity? A. Resistance is a response to a particular microbe. B. A response that is directed only against a particular microbe C. A system that protects us against trauma and disease D. Several nonspecific defenses present in all humans from the time of birth. 49. What is the name for the scientific study of how the immune system functions in the body to prevent or destroy foreign material, such as pathogens? A. Immunology B. Epidemiology C. Pathology D. Microbiology 50. The fluid portion of blood is A. lymph. B. serum. C. formed elements. D. clotting agents. 51. Neutrophils are those leukocytes that function A. in the production of antibodies. B. as manufacturers of clotting agents. C. as phagocytes in body resistance. D. to neutralize acidic environments. 52. The blood cell that contains cytotoxic granules that are particularly useful in killing multicellular parasites is the A. neutrophil. B. natural killer cells. C. eosinophil. D. monocyte. 52. Which of the following cells are leukocytes? A. Erythrocytes B. Platelets C. Thrombocytes D. Neutrophils 53. Which of the following cells are agranulocytes? A. Neutrophils B. Monocytes C. Eosinophils D. Basophils 54. All the following apply to the body's white blood cells except A. they have no pigment in their cytoplasm, so appear grayish when unstained. B. they are produced in the bone marrow. C. they carry oxygen to the tissues. D. they include cells that function in innate immunity and cells that function in acquired immunity. 55. Which of the following is true about both macrophages and neutrophils? A. Are phagocytes B. Have large granules in the cytoplasm C. Lack a nucleus D. Have a life span of about 10 years 56. A nonspecific leukocyte that destroys tumor cells and cells that are infected with viruses is the A. basophil. B. neutrophil. C. NK cell. D. monocyte. 57. Which of the following blood cells has the shortest life-span? A. Erythrocytes B. Neutrophils C. Monocytes D. Macrophages 58. Which of the following is not a lymphocyte? A. B cells B. T cells C. Monocytes D. NK cells 59. Which of the following leukocytes are involved in acquired immunity? A. Monocytes and macrophages B. Basophils and eosinophils C. Neutrophils and NK cells D. B lymphocytes and T lymphocytes 60. Which of the following is a primary lymphoid tissue? A. Spleen B. Thymus C. Lymph nodes D. Appendix 61. Which of the following are secondary lymphoid tissues? A. Lymph nodes B. Appendix C. Tonsils D. All of the above are correct. 62. All of the following are functions of the lymphatic system except A. forms an alternate pathway for blood circulation. B. maintains and distributes lymphocytes. C. monitors for pathogens. D. filters extracellular fluid before returning it to the circulatory system. 63. Which of the following is the function of secondary lymphoid tissues? A. Sites where immune cells form B. Where mature immune cells interact with pathogens and carry out the acquired immune response C. Returns body fluids to the circulatory system D. Responsible for the production of blood cells. 64. Locations in the body where mature immune cells interact with pathogens are likely to be in the A. membranes of the brain. B. lymph nodes and spleen. C. thymus gland. D. bone marrow where red cells are formed. 65. Which of the following organs is part of the mucosa-associated lymphoid tissues (MALT)? A. Peyer patches B. Lymph nodes C. Spleen D. All of the above are correct 66. The cells that have long, thin cytoplasmic extensions, are found in various body tissues and are very important in activation of lymphocytes are the A. Dendritic cells. B. Eosinophils. C. Neutrophils. D. T cells. 67. Innate immunity is the form of immunity that A. requires T and B lymphocytes. B. takes place only in the blood. C. responds quickly to many common microbial features but not to host features. D. occurs in the thymus 68. Lysozyme acts on bacteria by A. inhibiting protein synthesis in all bacteria. B. stimulating interferon production. C. destroying the cell wall of gram-positive bacteria. D. interfering with the motility of bacteria. 69. Which of the following are mechanical barriers in the body's first line of defense? A. Intact skin B. Lysozymes in tears C. Normal microbiota like Lactobacillus lining the vaginal tract D. Mucus lining the upper respiratory tract 70. Chemical barriers to infection include all of the following except A. stomach acid. B. defensins. C. mucus D. low pH of vaginal secretions. 71. A compound that digests the cell wall of gram positive bacteria is A. bile. B. lysozyme. C. interferon. D. stomach acid. 72. All of the following are true about chemical defensins except A. found and produced on the skin surface. B. produced by phagocytic cells. C. produced in the bone marrow. D. produced by epithelial cells that line the respiratory, gastrointestinal and urogenital tracts. 73. Which of the following protects against colonization of pathogens by taking up space and nutrients on the skin and mucosa? A. Nonpathogenic microbes that live on those surfaces B. Mast cells C. Sebum D. Phagocytes 74. When Metchnikoff put a splinter into the body of a starfish larva, he saw that it was soon surrounded by wandering cells. He was observing a process that today is described as A. neutralization. B. opsonization. C. escortation. D. phagocytosis. 75. What is a phagolysosome? A. When a phagocyte starts to produce lysosomes B. When a defensin starts producing hydrogen peroxide C. When a phagosome fuses with several lysosomes to digest a pathogen D. A structure formed during the respiratory burst following phagocytosis 76. Opsonins may be described as A. types of white blood cells that are especially efficient phagocytes. B. substances that enhance the efficiency of phagocytosis. C. short antibacterial peptides. D. types of bacterial exotoxins that destroy white blood cells. 77. Which one of the following is not a toxic substance within the phagolysosome? A. Nitric oxide (NO) B. Superoxide anion (O -) C. Chemokines D. Acid hydrolases 78. Chemokines are cytokines that A. activate the acquired immune response. B. .stimulate neutrophils to migrate to the site of an infection C. induce an antiviral state in a cell D. All the above are correct. 79. At the site of tissue damage and/or infection, tissue macrophages secrete cytokines that induce A. vasodilation and increased vascular permeability, allowing more cells and fluid into the area. B. destruction of cells in the area so that the infection does not spread. C. septic shock in the area. D. bleeding to increase the blood in the area. 80. Which of the following is not one of the four cardinal signs of inflammation? A. Redness B. Pain C. Swelling D. Bleeding. 81. A chemical circulating in the blood that causes a fever to develop is called a A. Pyogen. B. Pyrogen. C. Histamine. D. Perforin. 82. Pus is often found in infections. It is composed of A. fluid leaking out of the blood vessels. B. the digested material expelled from the phagocyte. C. dead and dying neutrophils and damaged tissues. D. fibrin clots. 83. All of the following are true about a low to moderate fever except A. it may be beneficial in immune defense. B. it may inhibit the rapid growth of pathogens. C. it may cause convulsion and death. D. it increases the body’s rate of tissue repair. 84. The function of the formation of a fibrin clot during an inflammatory response to a bacterial infection is to A. wall off the infecting bacteria to prevent their spread. B. poison the bacteria. C. signal a response from specific lymphocytes. D. enhance diapedesis. 85. Natural killer (NK) cells can be described by all of the following except A. NK cells have special receptors for target cells on the surface of their membrane. B. NK cells recognize the body’s cells and do not attack them. C. NK cells secrete several cytokines that trigger responses from macrophages and other cells. D. NK cells are phagocytes that rely on Class I MHC proteins to recognize the body’s cells. 86. NK cells secrete two enzymes that attack foreign, virus infected or cancerous cells. What are they? A. Histamine and lysozymes B. Perforin and granzymes C. Heparin and granzymes D. Pyrogen and lysozymes 87. All of the following statements are true about complement except A. it contributes to enhancement of the inflammatory response and phagocytosis. B. it may be activated by three different pathways. C. it is a single protein that circulates in the blood. D. it can lead to formation of the membrane attack complex. 88. Which one of the following is not an effect of complement activation? A. Production of substances that trigger an inflammatory response B. Lysis of pathogens C. Enhancement of T cell function through production of cytokines D. Opsonization 89. The innate immune system recognizes pathogens by identifying PAMPS, unique microbial molecular sequences that are not found on host cells. The receptors on macrophages, dendritic cells and endothelial cells that bind to these PAMPS are called A. chemokine receptors. B. toll-like receptors. C. opsonin receptors D. acute phase proteins #90. The theory of specific immunologic tolerance suggests that A. a person’s own cells do not stimulate an immune response. B. antibodies are produced by only one clone of cells. C. antigens tolerate self-destruction by phagocytes. D. antibodies react specifically with immunologic substances. 91. Antigenic determinants are the parts of antigen molecules that A. code for antibody molecules. B. stimulate phagocytosis. C. stimulate the immune system. D. clot blood. 92. Haptens are poor stimulators of immunity because haptens may be A. inability to perform cross-linking. B. too small to recognize the antigens at the receptor sites. C. unable to locate the proper B cell. D. easily digested by the phagocytes. 93. Which one of the following are not immunogenic? A. Components of bacterial capsules B. Flagella proteins C. Pilus protein D. Haptens 94. The cell-surface receptor on a B cell is a(n) A. molecule of polysaccharide. B. cluster of haptens. C. antigen. D. antibody molecule. 95. Which cells can develop into antibody producing cells? A. T lymphocytes B. B lymphocytes C. Dendritic cells D. Macrophages 96. The theory called clonal selection specifies that A. exposure to an antigen activates only those T- and B-cells with receptors recognizing specific epitopes on the antigen. B. the activation of Tcells produces antibodies that recognize epitopes. C. T cells are involved in the process by which antibodies are produced against epitopes. D. B cellsprovide resistance through direct cell-to-cell contact with and lysis of infected or otherwise abnormal cells. 97. The immune response to intracellular pathogens is controlled and regulated by A. T cells. B. B cells. C. dendritic cells. D. natural killer cells. 98. The theory of clonal selection refers to the A. activity of cytotoxic and helper T cells. B. activation of naïve lymphocytes with receptors for a certain epitope. C. conversion of plasma cell to B lymphocyte. D. reversion of clones of B lymphocytes to clones of selected T lymphocytes. 99. Which one of the following does not apply to plasma cells? A. They secrete antibodies. B. They are derived from B cells. C. They carry out their functions by producing cytokines. D. They are effector cells. 100. The ability to mount an efficient secondary antibody response depends on A. memory T and B cells. B. high concentrations of IgA antibody. C. cross-linking of IgM antibodies. D. All the above are correct. 101. T-lymphocyte stimulation by specific antigens leads to a type of immunity called A. cell-mediated immunity. B. antibody-mediated immunity. C. innate immunity. D. species immunity. 102. Which of the following cells undergo clonal selection when their antigen receptors bind to an antigen? A. B cells B. CD4 T cells C. CD8 T cells D. All of the above 103. The cell that matures in the thymus gland A. localizes in the skin tissues. B. becomes a plasma cell. C. is responsible for cell-mediated immunity. D. produces antibodies. 104. Which of the following cells has specific antigen receptors, has to interact with antigen presenting cells in order to be activated, and kills host cells that are infected with viruses? A. B cells B. Helper T cells C. Cytotoxic T cells D. Natural Killer cells 105. The thymus A. is where lymphoid progenitor cells mature into immunocompetent T cells. B. is where B cells mature into plasma cells. C. selectively destroys B lymphocytes. D. is involved in the humoral immune response. 106. The site on an antibody molecule that can be bound by a phagocyte is part of the A. Fab fragment. B. variable region. C. light chain. D. Fc fragment. 107. The portion of the immunoglobulin molecule that contains the antigen binding site can be described as all of the following, except A. composed of parts of the light chain and the heavy chain. B. is called the Fab fragment. C. composed of variable domains. D. is called the Fc fragment. 108. Which of the following are functions of the Fc fragment? A. It can combine with phagocytes in opsonization. B. It may activate the complement system in resistance mechanisms. C. It might attach to certain cells in allergic reactions. D. All of the above are correct. 109. An antibody is a protein composed of A. a single polypeptide chain. B. a heavy polypeptide chain joined to a light polypeptide chain. C. two heavy polypeptide chains with each joined to a light polypeptide chain. D. two identical polypeptide chains. 119. All of the following are true of IgG except A. it confers immunity to the fetus. B. it is the important factor of the secondary antibody response. C. it is the major circulating antibody. D. it is critically important in allergic reaction. 111. The antibody class is referred to as the maternal antibody. A. IgM B. IgA C. IgE D. IgG 112. The first antibody produced in a primary antibody response is A. IgG. B. IgM. C. IgA. D. IgD. 113. Colostrum contains A. IgG. B. IgM. C. IgA. D. IgD. 114. Which of the following is NOT true about the secondary response to a particular antigen? A. Faster than the primary response B. Higher antibody titer than the primary response C. Memory cells are involved D. Happens the first time the antigen stimulates the lymphocytes 115. Antibodies can protect against viral infection by binding to epitopes on the viruses which A. kills the virus. B. prevents the virus from attaching to host cells. C. causes agglutination of the viral particles. D. None of the above: antibodies offer no protection against viruses. 116. The neutralization of toxin molecules by antitoxins accomplishes all the following except A. increases the activity between toxins and interleukins. B. prevents toxin from binding to cells. C. prevents toxic effects on cells. D. lessens the ability of toxins to diffuse through the tissues. 117. Antibodies binding to antigens can trigger A. opsonization. B. activation of complement. C. neutralization. D. All the above are correct. 118. Macrophages are involved in A. presenting antigen fragments to T cells. B. phagocytosis. C. destroying antigen-antibody complexes. D. All the above are correct. 119. Which one of the following is not an effect of complement activation? A. Lysis of a bacterial cell through cytoplasmic leakage B. Attraction of phagocytes C. Enhanced T-lymphocyte activity through thymus gland interaction D. Opsonization of bacterial surfaces 120. CD8 co-receptor proteins are found on A. helper T cells. B. macrophages. C. cytotoxic T cells. D. plasma cells. 121. CD4 co-receptor proteins are found on A. helper T cells. B. macrophages. C. cytotoxic T cells. D. plasma cells. 122. Which of the following molecules are found on the surface of all nucleated cells in the body? A. Immunoglobulin B. MHC Class I molecules C. MHC Class II molecules D. TCRs 123. Which of the following molecules are only found on the surface of antigen presenting cells? A. Immunoglobulin B. MHC Class I molecules C. MHC Class II molecules D. TCRs 124. Which one of the following is not associated with interleukin-1? A. It is secreted by macrophages. B. It activates helper T cells. C. It stimulates antigen-antibody reactions. D. It is produced in response to APC binding to T cell. 125. The cells that are responsible for killing abnormal cells such as tumor cells are A. Phagocytes such as macrophages. B. Helper T cells. C. Cytotoxic T lymphocytes. D. B cells. 126. Cytotoxic T cells release which of the following cytokines in cell to cell combat? A. Lysozyme and histamine B. Perforin and granzyme C. Lysozyme and perforin D. Granzyme and histamine 127. The only cells required in an antibody response to T-independent antigens are A. B lymphocytes. B. T lymphocytes. C. natural killer cells. D. macrophages. 128. Superantigens are A. antigens that bind directly to MHC protein on T cells. B. extraordinarily large antigens on B cells. C. haptens + carrier proteins. D. None of the above are correct. #129. With the development of modern vaccines we have brought which of the following diseases to the point where we can now say it has been eradicated? A. Smallpox B. Polio C. Diptheria D. Pertussis 130. How does an individual gain naturally acquired active immunity? A. Get the disease and recover from it. B. Be exposed exposed to the disease, but have a subclinical case. C. Be born with a natural immunity to the disease. D. Both A and B are correct, but not C. 131. An individual generally acquires natural active immunity after A. an injection of IgG. B. an infusion of T lymphocytes. C. a blood transfusion. D. suffering an illness. 132. Active immunity develops after the A. antigens enter the body and induce an immune response. B. antiserum is injected into the body. C. antibodies pass across the placenta to the fetus. D. antibodies pass in the colostrum to the newborn. 133. Which of the following types of vaccines induce the strongest immune response, sometimes giving a lifelong immunity? A. Conjugate vaccine B. DNA vaccine C. Live attenuated vaccine D. Recombinant subunit vaccine 134. The intentional injection of an attenuated virus into a person will lead to A. naturally acquired active immunity. B. artificially acquired active immunity. C. naturally acquired passive immunity. D. artificially acquired passive immunity. 135. The Sabin oral polio vaccine is prepared with polioviruses that stimulate the immune system. A. activated B. attenuated C. killed D. parts of 136. Attenuated viral vaccines are more difficult to use in developing countries than inactivated viral vaccines because A. they require more booster shots. B. they require refrigeration to retain their effectiveness. C. it is difficult finding enough sterile needles for them. D. it is difficult finding enough medical personnel to administer the vaccines. 137. Which of the following is a drawback to the use of inactivated vaccines? A. Booster shots are required to maintain immunity for long periods of time. B. They have to be kept refrigerated. C. They have a short shelf life. D. All of the above are correct. 138. Immunity to the disease may be stimulated by injection of a preparation of . A. pertussis; attenuated viruses B. meningitis; inactivated virus C. diphtheria; toxoid D. measles; bacterial fragments 139. Which of the following is a single-dose vaccine? A. Sabin polio vaccine B. Diphtheria-tetanus-acellular pertussis (DTaP) vaccine C. Salk polio vaccine D. All of the above are single-dose vaccines. 140. Subunit vaccines are those that use A. parts of antibody molecules as antigens. B. fragments of phagocytes in solution. C. parts of microorganisms such as pili and capsular polysaccharides. D. preparations of haptens. 141. Conjugate vaccines contain toxoids because A. toxoids are much easier to store. B. polysaccharide antigens by themselves produce a weak immune response. C. they are only used for diseases caused by toxins. D. the pathogen that they are designed to protect against has no other antigens. 142 Which of the following vaccines are conjugate vaccines where part of the capsular polysaccharides are added to a tetanus or diphtheria toxoid? A. Hib B. MMR C. Salk polio D. Sabin polio 143. Recombinant subunit vaccines have been developed against A. polio. B. hepatitis B. C. tetanus. D. None of the above is correct. 144. Passive immunity can A. involve an injection of antibodies. B. be acquired by a child from its mother. C. be administered with a convalescent serum. D. All the above are correct. 145. A child receiving antibodies in the colostrum during nursing has acquired immunity that is A. passive and active. B. natural and artificial. C. passive and natural. D. artificial and passive. 146. Serum sickness may accompany the development in the body of A. cell-mediated immunity. B. the complement cascade. C. artificial passive immunity. D. natural active immunity. 147. When the immune system recognizes a foreign protein in a serum injection, immune complexes form and complement is activated, a person may develop a type of reaction called A. immune complex disease. B. anaphylaxis. C. hypersensitivity. D. serum sickness. 148. Which one of the following is not a characteristic of convalescent serum? A. It protects against an illness. B. It is derived from the blood of a patient recovering from an illness. C. It is used to treat an established disease. D. It is made from a pool of sera from animals. 149. Herd immunity is affected by all the following factors except A. the environment. B. antibiotic use. C. immune system strength. D. the number of vaccinated people in the population. 150. Which one of the following is not related to antibody titer? A. The amount of antibodies present in the serum B. The progress of a disease C. The level of immunity in a patient D. The degree of activity of T lymphocytes 151. A neutralization reaction may be observed in the laboratory by A. noting the agglutination of red blood cells. B. injecting the antigen-antibody mixture to an animal. C. watching for precipitate formation. D. observing the fixing of complement. 152. You are carrying out a serological test. You first mix a sample of diphtheria toxin with the patient's serum, inject it into a mouse, then watch to see whether the animal dies or survives. You have performed a(n) A. precipitation test. B. neutralization test. C. agglutination test. D. complement fixation test. 153. Precipitation reactions between antigens and antibodies are characterized by A. appearance of IgE in the immune system. B. formation of a large lattice formed from antibodies and antigens. C. inhibition of the complement system. D. destruction of red blood cells. 154. The zone of equivalence is the A. concentrations of antibodies and antigens which is ideal for precipitation. B. area on an immunoelectrophoresis gel where the antibody is placed C. optimum concentration of vaccine for an individual. D. time at which active and passive immunity are equally effective in protecting against disease. 155. A neutralization test for diphtheria is called A. Coombs test. B. Widal test. C. Schick test. D. precipitin test. 156. In immunodiffusion, antigens and antibodies diffuse through a gel towards each other and A. agglutinate when they reach each other. B. neutralize each other. C. form a visible precipitate at the zone of equivalence. C. fluoresce at the zone of equivalence. 157. The test to detect Rh antibodies is the A. Coombs test. B. Widal test. C. Schick test. D. precipitin test. 158. At the conclusion of the complement fixation test, the person performing the test observes whether A. red blood cells undergo lysis. B. precipitates of toxin form. C. phagocytosis increases in rate. D. the tests animals live or die. 158. All the following are required to perform a florescent antibody test for syphilis except A. a sample of the patient's serum. B. fluorescein-labeled antiglobulin antibodies. C. complement from a guinea pig. D. syphilis spirochetes. 160. An important advantage of the radioimmunoassay is the A. adaptability to small laboratories. B. high sensitivity. C. low hazard level. D. low cost per test. 161. The results of an enzyme linked immunosorbent assay (ELISA. for HIV are determined by noting A. agglutination of antigens and antibodies. B. whether or not an animal lives after an injection. C. a neutralization of toxins by antitoxins. D. a color change in the reagents. 162. Which of the following methods can quantify the amount of antibody based on the change in color in the test system? A. RIA B. ELISA C. Ouchterlony test D. Immunoelectrophoresis 163. Which of the following is used in indirect fluorescent antibody techniques but not in direct fluorescent antibody techniques? A. A labeled antibody B. Antihuman antibodies C. An antigen D. Rhodamine 164. RAST is a type of A. Fluorescent antibody test. B. Precipitin test. C. ELISA test. D. Radioummunoassay test. 165. Polyclonal antibodies in serum arise from A. a single clone of B cells. B. a mixture of vaccines. C. several clones of B cells. D. several clones of T cells. 166. Which of the following is NOT true of monoclonal antibodies? A. Produced from a hybridoma B. Highly specific C. Used as reagents D. Result from subunit vaccines *167. The antigenic substance that sets off anaphylactic reaction A. interacts with the body's T lymphocytes. B. is known as an allergen. C. induces smooth muscle contraction directly. D. contains cyclic AMP molecules. 168. Which one of the following does not apply to basophils? A. They are a type of white blood cell. B. They are rich in granules that contain histamine. C. They represent about 1 percent of the total white blood cell count. D. They contain hemoglobin for oxygen transport. 169. During the sensitization phase of immediate hypersensitivity, A. complement is activated. B. most cells and basophils degranulate. C. smooth muscles contract. D. IgE molecules attach to basophils and mast cells. 170. IgE is the antibody involved in hypersensitivity. A. type I B. cellular C. immune complex D. type II 171. An allergen is a(n) A. antibody produced in anaphylactic hypersensitivity. B. antigen that initiates an allergic reaction. C. antigen that induces cell-mediated immunity. D. antibody produced in response to autoantigen. 172. Which one of the following is a product made and released by mast cells sometime after degranulation? A. Leukotrienes B. Cyclic AMP C. TNF alpha D. Interleukin-4 173. Anaphylaxis would fail to occur without A. release of mediators from mast cells and basophils. B. formation of immune complexes. C. fixation of complement on the walls of blood vessels. D. accumulation of IgG in the affected tissues. 174. A life-threatening situation in anaphylaxis occurs when A. gastrointestinal cramps take place. B. hives appear on the skin. C. bronchiole muscles contract. D. the brain swell with fluid. 175. In an anaphylactic reaction, onstriction of the small veins and expansion of the capillary pores forces fluids out into the tissues causing A. a rash consisting of both wheals and flares. B. wheezing and stressed breathing. C. the skin to become swollen about the eyes, wrists, and ankles. D. IgG to form complexes with antigens near the site of the latter's entry into the body. 176. Food allergies are a form of hypersensitivity. A. Type I B. Type II C. Type III D. Type IV 177. No antibodies are involved in hypersensitivity. A. type I B. cytotoxic C. immune complex D. cellular 178. A series of events in which mediators cause all the body's smooth muscles to undergo vigorous contractions is called A. common allergy. B. asthma. C. anaphylaxis. D. infection allergy. 179. Which of the following events does not occur during systemic anaphylaxis? A. Degranulation of mast cells throughout the body B. Contraction of smooth muscles in the body C. Constriction of the small veins and the expansion of capillary pores D. Release of cytotoxins from T lymphocytes 180. The major preformed mediator in the granules of mast cells is A. Complement B. Histamine C. Leukotrienes D. IgE 181. What triggers mast cells to degranulate in an allergic reaction? A. Complement binding to the cell membrane B. Cross-linking of the IgE by allergen C. Antihistamines used in the treatment of the symptoms D. Cytokines produced by Th cells 182. Which of the following substances can trigger an asthma attack? A. Pollen and mold spores B. Dust mites and pet dander C. Cold temperatures D. All of the above are correct. 183. One of the objects of desensitization procedures is to A. stimulate the production of interferon. B. destroy immune complexes that may have formed in the blood vessels. C. decrease the level of IgE. D. stimulate the production of antihistamines. 184. Which one of the following applies to a cytotoxic hypersensitivity? A. IgG reacts with antigens on the surfaces of cells. B. An induration develops at the site of contact with antigen. C. IgE fixes itself to the basophil surface. D. Poison ivy induces 185. Hemolytic disease of the newborn is primarily a result of A. formation of immune complexes in the tissues. B. antibodies from the mother attaching to antigens located on the baby’s red blood cell surface. C. decreased phagocytosis arising from thrombocytopenia. D. reaction between toxins and antitoxins occurring in the blood vessels. 186. If a woman with blood type A-positive has a child by a man whose blood type is A-negative A. the child will have type B blood. B. hemolytic disease may occur in the second child to be conceived. C. the child will not suffer from hemolytic disease nor will a future child. D. the woman will develop Rh antibodies at the conclusion of pregnancy. 187. Hemolytic disease of the newborn may result when which of the following couples have children? A. An Rh (+) man and an Rh (+) woman B. An Rh (+) man and an Rh (-) woman C. An Rh (-) man and an Rh (+) woman D. An Rh (-) man and an Rh (-) woman 188. T lymphocytes are the mediators of hypersensitivity. A. anaphylactic B. cytotoxic C. immune complex D. delayed 189. All of the following are associated with type IV hypersensitivity reactions except A. an induration. B. accumulation of T lymphocytes at the antigen site. C. production of IgE. D. infection allergy. 190. Repeated exposure to allergenic shampoos may lead to drying and scaling of the scalp. This is an example of A. infection allergy. B. contact dermatitis. C. common allergy. D. cytotoxic hypersensitivity. 191. Which one of the following is not involved in systemic lupus erythematosus? A. Immune complex formation B. A butterfly rash C. Autoantigens and autoantibodies D. Mediators such as histamine 192. Systemic lupus erythematosus is an autoimmune disease that is an example of a(an) hypersensitivity. A. anaphylactic B. cytotoxic C. immune complex D. cellular 193 An isograft has less chance of rejection than a xenograft because A. the isograft is not composed of living tissue. B. new blood vessels need not be formed in the isograft. C. the graft composition of the donor and recipient are identical in an isograft. D. there are no antigens in an isograft. 194. Identification of the major histocompatibility proteins is helpful in determining A. the nature of autotoxins produced by the immune system. B. the extent of a person's allergy. C. the expected acceptance or rejection of transplanted tissue. D. whether a woman is Rh-positive or Rh-negative. 195. Which molecules are the major targets seen as foreign by the recipient’s immune system in rejection of allografts? A. HLA B. Histamine C. T cell receptor D. Antibodies 196. Transplanted tissue is rejected by the body if the A. grafted tissue is an autograft. B. blood types of donor and recipient are the same. C. immune system interprets the tissue to be nonself. D. donor and recipient of the transplant are identical twins. 197. Which type of graft rejection is due to preformed antibodies? A. Acute B. Hyperacute C. Chronic D. None of the above, since all transplant rejection is mediated by T cell. 198. DiGeorge syndrome and Bruton's agammaglobulinemia are both A. characterized by cytotoxic reactions. B. immune deficiency diseases. C. autoimmune diseases. D. types of atopic reactions. 199. A primary immunodecificiency in which B cells fail to develop into immunocompetent cells is A. DiGeorge syndrome. B. Bruton's agammaglobulinemia. C. Arthus phenomenon. D. Graves' disease. 200. The most dangerous of the following immune system diseases is A. atopic disease. B. severe combined immunodeficiency. C. systemic lupus erythematosus. D. allergic rhinitis. 201. Chédiak-Higashi syndrome and chronic granulomatous disease are both linked to A. defects in the body's phagocytes. B. autograft rejection. C. a delayed hypersensitivity reaction. D. the development of an induration. 202. causes AIDS. A. Influenza virus B. Streptococcus pneumoniae C. HIV D. Noroviruses 203. AIDS stands for A. Acquired Immunodeficiency Syndrome. B. Acquired Immunodeficiency Symptom. C. Acquisitioned Immunosuppressing Syndrome. D. Autoimmune Deficiency Syndrome. 204. Which of the following is not part of an HIV particle? A. CD4 receptors B. Gp120 proteins C. Reverse transcriptase D. Gp41 205. Within 72 hours of infection of a host cell, the reverse transcribed HIV DNA molecule has integrated into one of the host chromosomes as a . A. plasmid B. plastid C. prion D. provirus 206. Which enzyme uses the viral RNA as a template to synthesize a strand of DNA and then uses the DNA strand as a template to complete a DNA double helix? A. DNA ligase B. Reverse transcriptase C. RNA polymerase D. DNA polymerase 207. Stage is the asymptomatic stage of HIV infection. A. I B. II C. III D. IV 208. Stage IV is also known as the late or stage of HIV infection. A. latent B. AIDS C. progressive D. prodromal 209. is/are the hallmark of HIV infection. A. Opportunistic infections B. T cell proliferation C. Immune stimulation D. None of the above. 210. T-cell counts of or less defines an HIV-infected individual as having AIDS. A. 200 B. 500 C. 1,000 D. 10,000 211. HIV can be transmitted by “risky behaviors” such as . A. unprotected sexual contact with an HIV-infected person B. sharing contaminated needles with an HIV-infected person C. oral sex with an HIV-infected person D. All of the above. 212. Diagnosis of HIV infection often relies on the detection of HIV in the blood. A. particles B. antibodies C. proteins D. reverse transcriptase *213. Alexander Fleming is credited with the discovery of which of the following antimicrobial agents? A. Quinine B. Penicillin C. Cephalosporin D. Erythromycin 214. Which of the following is the best definition of an antibiotic? A. A chemical that is made in the pharmaceutical laboratory that kills or inhibits other microorganisms B. A product produced by living microorganisms that kills or inhibits other microorganisms C. Any chemotherapeutic agent that harms an infectious organism D. The concentration of the drug that destroys the pathogen 215. A semisynthetic antibiotic is one that is A. made in a pharmaceutical laboratory. B. produced by a species of mold or bacteria. C. partly of microbial origin and partly of laboratory origin. D. partly functionally. 216. A broad spectrum antibiotic would be expected to be effective against A. Gram positive bacteria only. B. Gram negative bacteria only. C. both Gram positive and Gram negative bacteria. D. both bacteria and viruses. 217. Ideally, an antimicrobial agent should exhibit selective toxicity, meaning that A. it should harm the infectious agent but not the host. B. it should have very low toxic dose. C. it should have a very high therapeutic dose. D. it should be toxic to a wide variety of infectious agents. 218. Sulfonamide is a competitive inhibitor which interferes with the ability of a bacteriujm to A. resist the effect of tetracycline. B. synthesize PABA. C. undergo transformation to a resistant form. D. form folic acid. 219. Isoniazid is a narrow spectrum antibiotic that is useful for treatment of A. viral infections. B. pneumonia. C. tuberculosis. D. strep throat. 220. Isoniazid inhibits the synthesis of A. peptidoglycan. B. folic acid. C. mycolic acid. D. viral RNA. 221. Which group of antibiotics block DNA synthesis in bacteria? A. Quinolones B. Penicillins C. Aminoglycosides D. Tetracyclines 222. The two major drawbacks to the use of penicillin are A. kidney damage and immune complex formation. B. allergic reactions and development of drug-resistant bacteria. C. aplastic anemia and anaphylactic hypersensitivity. D. loss of hearing and cytotoxic hypersensitivity. 223. A person who is allergic to penicillin allergy may be treated with A. bacitracin but not cephalosporin. B. erythromycin but not ampicillin. C. amoxicillin but not erythromycin. D. ampicillin but not amoxicillin. 224. The beta lactam nucleus is the basic structure of A. penicillin. B. tetracycline. C. chloramphenicol. D. aminoglycosides. 225. Penicillin is most effective against A. log phase gram (-) bacteria. B. stationary phase gram (-) bacteria. C. log phase gram (+) bacteria. D. stationary phase gram (+) bacteria. 226. Both the cephalosporin and penicillin antibiotics A. are produced by mold-like bacteria. B. are used primarily for gram-negative bacteria. C. act on the cell wall of bacteria. D. are related to sulfanilamide. 227. Cephalosporins act by A. inhibiting protein synthesis. B. interfering with cell-wall biosynthesis. C. competitively inhibiting folic acid biosynthesis. D. inhibiting RNA synthesis. 228. Members of the genus Streptomyces A. produce sulfanilamide. B. are commonly found in the urinary tract. C. produce many well-known antibiotics. D. are used to test the MIC of an antibiotic. 229. A common feature of bacitracin and polymyxin B is that both antibiotics A. are effective against fungi. B. contain four benzene rings and several carbohydrate side-groups. C. are only used topically. D. lead to anaphylaxis reactions. 230. All aminoglycoside antibiotics function by A. interfering with cell wall synthesis. B. attaching irreversibility to bacterial ribosomes. C. blocking absorption at the cell membrane. D. blocking DNA transcription. 231. The tubercle bacillus is usually susceptible to A. erythromycin but not streptomycin. B. streptomycin but not penicillin. C. penicillin but not nystatin. D. cephalothin but not isoniazid. 232. Chloramphenicol A. inhibits RNA synthesis. B. cannot be absorbed from the intestine. C. interferes with protein synthesis in microorganisms. D. is effective only against gram (-) infections. 233. All the following apply to the tetracycline antibiotics except A. they are associated with discoloration of the teeth. B. they are used for rickettsial and chlamydial diseases. C. they are broad-spectrum antibiotics. D. they may cause aplastic anemia or the gray syndrome. 234. The spectrum of activity of tetracycline antibiotics A. includes the viruses. B. is limited to the fungi. C. includes viruses, protozoa, and fungi. D. includes Rickettsia and Chlamydia. 235. Pseudomembranous colitis is a condition of the intestine that may be related to A. the anaphylaxis associated with penicillin. B. aplastic anemia. C. overuse of lincomycin and clindamycin. D. cell-wall inhibition caused by vancomycin. 236. Penicillins interfere with the synthesis of A. folic acid. B. peptidoglycan. C. DNA. D. mRNA. 237. Some bacteria produce beta-lactamases, which break down and inactivate A. penicillins. B. macrolides. C. fluoroquinolones. D. tetracyclines. 238. Nystatin is the recommended drug for A. infections of the intestine due to gram-negative bacteria. B. viral infections of the skin. C. malaria and tuberculosis. D. Candida albicans infections of the intestine or oral cavity. 239. Flucytosine, clotrimazole, and ketoconazole are all A. drugs for treating leprosy. B. modern sulfonamide drugs. C. antifungal agents. D. cell wall inhibitors. 240. Chloroquine, primaquine, and quinine are of value for the treatment of A. urinary tract infections. B. cases of malaria. C. infections caused by bacteria of the intestinal tract. D. fungal diseases. 241. Which of the following is not a type of chemotherapeutic agent used to treat viral infections? A. Agents which inhibit reverse transcriptase B. Agents which inhibit proteases C. Agents which are base analogs D. Agents which interfere with ergosterol 242. The Kirby-Bauer test is useful for determining A. the minimum inhibitory concentration of an antibiotic. B. whether side effects will result from use of an antibiotic. C. which antibiotic may be employed to treat an infection. D. the origin of an antibiotic. 243. Which of the following factors contribute to the selection of antibiotic resistant bacteria? A. Using antibiotics when they are not needed B. Failing to complete a course of treatment C. Antibiotics given to livestock D. All of the above. Section B. Matching - 1 Select one of the following four virulence factors to correctly complete each of the statements in the following questions. A. Hyaluronidase B. Exotoxin C. Coagulase D. Endotoxin 244. sometimes is called the spreading factor. Ans: A 245. is a product of metabolism in many gram-positive bacteria. Ans: B 246. is part of the cell wall of gram-negative bacteria. Ans: D 247. is produced by virulent staphylococci. Ans: C 248. elicits the production of antitoxins. Ans: B 249. enhances resistance to phagocytosis by forming a clot. Ans: C 250. may be altered to form toxoids. Ans: B 251. digests hyaluronic acid to its component molecules. Ans: A 252. contributes to the invasiveness of an organism. Ans: A 253. consists of part of the outer membrane of the cell wall. Ans: D 254. may cause circulatory damage and shock. Ans: D 255. is identified by combining staphylococci with rabbit plasma. Ans: C 256. is released when the organism is killed. Ans: D Section B. Matching - 2 Select one of the following four choices to correctly complete each of the statements below. A. Inflammation B. Natural killer cells C. Phagocyte D. Eosinophil 257. was first described by Elie Metchnikoff. C 258. can move out of the circulation to engulf foreign particles or pathogens C 259 results in redness, heat, pain, and swelling. A 260. may develop from mechanical injury such as a blow to the skin. A 261. attack cells when MHC proteins are absent. B 262. contain granules that contain toxic compounds to defend against multicellular parasites, such as flukes and tapeworms D 263. is inhibited by a bacterial capsule. C 264. involves granzymes and perforins. B Section B. Matching - 3 Choose the category of acquired immunity that fits each of the following. A. Naturally acquired active immunity B. Artificially acquired active immunity C. Naturally acquired passive immunity D. Artificially acquired passive immunity 265. may result from an incident of subclinical disease. - Ans: A 266. arises from the passage of maternal antibodies. - Ans: C 267. results from an injection of hyperimmune serum. Ans: D 268. develops after treatment with antitoxin. Ans: D 269. follows a case of disease. Ans: A 270. may lead to serum sickness. Ans: D 271. provides protection for the first six months of life. Ans: C 272. can be raised to a higher level by booster shots. Ans: B 273. person becomes ill and produces own antibodies. Ans: A 274. follows unintentional exposure to antigens. Ans: A 275. arises from antibodies in the colostrum. Ans: C 276 follows an injection of attenuated virus. Ans: B 277. also is called congenital immunity Ans: C 278. produces memory cells from illness responsible for antibody production. Ans: A 279. is stimulated by inactivated viruses. Ans: B 280. is an intentional exposure to an immunizing agent and is long-lasting. Ans: B 281. can be induced in a nursing child. Ans: C 282. involves exposure to inactivated or attenuated viruses. Ans: B Section B. Matching – 4 Match each antimicrobial agent with its mode of action. A. Competitive inhibition B. Inhibits RNA synthesis C. Inhibits protein synthesis D. Inhibits function of cell membrane E. Inhibits cell wall synthesis F. Affects protozoal metabolism G. Interferes with mitosis 283. Penicillin Ans: E 284. Sulfanilamide Ans: A 285. Erythromycin Ans: C 286. Chloramphenicol Ans: C 287. Rifampin Ans: B 288. Cephalosporin Ans: E 289. Polymyxin Ans: D, E 290. Griseofulvin Ans: G, E 291. Chloroquine Ans: F, E Section B. Matching – 5 Select one of the following two choices to correctly match the description A. Humoral immunity B. Cell-mediated immunity 292. involves helper and cytotoxic T lymphocytes. Ans: B 293. is mediated by B cells that mature in the bone marrow. Ans: A 294. provides resistance to tuberculosis and viral infected cells. Ans: B 295. is characterized by the release of interleukins. Ans: B 296. involves the production of antibodies. Ans: A 297. involves granzymes and perforins Ans: B 298. involves plasma cells produced from B lymphocytes. Ans: A 299. is activated by a B cell binding specific antigen. Ans: A 300. involves cytotoxic T lymphocytes attacking virus-infected cells. Ans: B 301. produces five classes of immunoglobulins. Ans: A 302. requires T cell maturation through the secretion of IL-2. Ans: B 303. requires antigenic peptides to be bound to MHC proteins. Ans: B Section B. Matching – 6 Match each description with the correct term. A. CD8 coreceptor B. Epitopes C. Dendritic cells D. Interleukin-1 E. Interleukin-2 F. CD4 co-receptor G. Perforin H. Opsonin 304. Antigen presenting cells Ans: C 305. Attached to the surface of helper T cells Ans: F 306. Secreted by macrophages to stimulate T cells Ans: D 307. Antibody or complement protein that encourages phagocytosis Ans: H 308. Attached to the surface of cytotoxic T cells Ans: A 309. Antigenic determinants Ans: B 310. Stimulates T cells to divide and mature Ans: E 311. Toxin released by cytotoxic T lymphocytes Ans: G Section B. Matching – 7 Match each description with its immunoglobulin. A. IgG B. IgA C. IgM D. IgE E. IgD 312. higher levels indicates a very recent infection Ans: C 313. provides protection in the respiratory and gastrointestinal tracts Ans: B 314. major circulating antibody Ans: A 315. maternal antibody that crosses the placenta Ans: A 316. important in allergic reactions Ans: D Section B. Matching – 8 Select one of the following types of hypersensitivity to correctly complete each of the statements below. A. Type I anaphylactic hypersensitivity B. Type II cytotoxic hypersensitivity C. Type III immune complex hypersensitivity D. Type IV cellular hypersensitivity 317. is typified by the transfusion reaction. Ans: B 318. may be related to the development of rheumatic fever. Ans: C 319. requires IgE attached to mast cells. Ans: A 320. is the reaction to poison ivy. Ans: D 321. is due to deposits aggregates of antigens and antibodies on tissue surfaces. Ans: C 322. involves an exaggeration of the process of cellular immunity. Ans: D 323. may be accompanied by contractions of the GI tract, edema and shortness of breath. Ans: A 324. is typified by the Arthus reaction. Ans: C 325. does not involve antibody formation. Ans: D 326. involves histamine release. Ans: A 327. involves the degranulation of sensitized cells. Ans: A 328. involves an IgG reaction with antigens that may cause serum sickness. Ans: C 329. may lead to death in 10 to 15 minutes from asphyxiation if the reaction is systemic. Ans: A 330. involves IgG reacting with antigens on the surfaces of cells. Ans: B Section B. Matching- 9 Match each type of transplant rejection with the appropriate description A. Hyperacute rejection B. Acute rejection C. Chronic rejection 331. occurs within minutes of the transplant Ans: A 332. ongoing immune response due to minor antigenic differences Ans: C 333. due to preformed antibodies Ans: A 334. occurs within 10-30 days after the transplant and may be prevented by careful MHC matching and immunosuppressive therapy Ans: B 335. results in rapid destruction of the blood vessels of the graft Ans: A Section C. True/False - 1 336. True or False? When the natural resistance is unable to overcome the aggressiveness of microorganisms, disease sets in. Ans: True 337. True or False? Organisms in a commensalistic relationship with the human body derive benefit from the body but neither harm nor benefit the body. Ans: True 338. True or False? Parasites vary greatly in their pathogenicity. Ans: True 339. True or False? Acute diseases are those that take a long time to develop and then linger for long periods in the body. Ans: False Response: Chronic diseases are those that take a long time to develop and then linger for long periods in the body. 340. True or False? The incubation period of a disease reflects the time that passes between entry of the parasite to the host and the decline of the disease. Ans: False Response: The incubation period of a disease reflects the time that passes between entry of the parasite into the host and the appearance of symptoms. 341. True or False? The number of organisms that must be taken into the body for disease to occur is essentially the same for all infectious agents. Ans: False Response: The number of organisms that must be taken into the body for disease to occur varies between different infectious agents. 342. True or False? In a subclinical infection, few symptoms are evident in the patient, whereas in a clinical infection, the symptoms are apparent. Ans: True 343.. True or False? All pathogens have a single portal of entry into to the host that allows it to infect and cause disease. Ans: False Response: Some pathogens have more than one portal of entry into to the host that allows it to infect and cause disease. 344. True or False? Altered endotoxins may be used as immunizing agents because they induce the body to produce special antibodies called antitoxins. Ans: False Response: Altered exotoxins may be used as immunizing agents because they induce the body to produce special antibodies called antitoxins. 345. True or False? Coagulase-positive staphylococci resist body defenses by surrounding themselves with a fibrin clot, thereby escaping phagocytosis. Ans: True 346. True or False? Leukocidin is a product of the body's white blood cells that reacts with bacteria and dissolves them, thereby destroying the bacteria. Ans: False Response: Leukocidin is a product of bacteria that destroys leukocytes 347. True or False? In noncommunicable diseases, the infectious agent is usually acquired from the environment and is not easily transmitted to the next host. Ans: True 348. True or False? Mechanical vectors are arthropods that carry microbes on their body parts from one host to another, but are not infected with the microbe themselves. Ans: True 359. True or False? Direct methods for the transmission of disease include consumption of contaminated food or water, an arthropod bite, and contact with fomites. Ans: False Response: Indirect methods for the transmission of disease include consumption of contaminated food or water, an arthropod bite, and contact with fomites. 350. True or False? An arthropod that is infected with a certain parasite and that can transmit that parasite to a new host is considered a mechanical vector. Ans: False Response: An arthropod that is infected with a certain parasite and that can transmit that parasite to a new host is considered a biological vector. 351. True or False? Reservoirs of infection include animals, humans, water, and soil. Ans: True 352. True or False? The most common nosocomial infections are infection of surgical wounds, or infections to the respiratory, urogenital, or gastrointestinal tracts. Ans: True 353. True or False? Nosocomial infections are often caused by breaches of infection control practices and procedures, unclean and non-sterile environmental surfaces, and/or ill employees. Ans: True Section C. True/False – 2 354. True or False? Innate immunity, consists of several nonspecific defenses present in all humans from the time of birth. True 355. True or False? The polymorphonuclear neutrophils, monocytes, and macrophages are primarily concerned with phagocytosis. True 356. True or False? The lymphocyte is a leukocyte with a single nucleus that exists in the lymph nodes and functions in the immune system. True 357. True or False? Innate immunity develops over the course of the infection, taking several days to more than a week to mount an effective response and a protective defense. False Response: Acquired immunity develops over the course of the infection, taking several days to more than a week to mount an effective response and a protective defense. 358. True or False? A natural barrier to the intestine is provided by the extremely alkaline environment of the stomach contents. False Response: A natural barrier to the intestine is provided by the extremely acidic environment of the stomach contents. 359. True or False? A mixture of plasma dead tissue cells, leukocytes, and dead bacteria enclosed in a wall of fibrin yields an abscess or boil. True 360. True or False? The internalization of a microbe into phagocyte is enhanced when the microbe is coated with certain serum proteins, such as antibodies or complement. These protein molecules, called opsonins, attach to microbes and increase the ability of phagocytes to adhere to the pathogen. True 361. True or False? The immune system responds to invasion by pathogenic microbes by mounting a rapid innate response, followed several days later by the development of antibodies and lymphocytes as part of the acquired immune response. True 362. True or False? Toll-like receptors (TLRs) are signaling receptors on macrophages, dendritic cells, and endothelial cells membrane that accelerate the formation of phagolysosomes and faster killing of engulfed microbes. True Section C. True/False – 3 363. True or False? In the preparation of toxoids, the antigenicity of the toxin remains while the toxigenicity is destroyed. Ans: True 364. True or False? A danger of subunit vaccines is that disease may occur in an immuno-incompetent pe