Chapter 15 MULTIPLE CHOICE Choose the one alternative that best completes the statement or answers the question 1 Which of the following does NOT contribute to the symptoms of a fungal disease A cell walls B toxins C allergic response of the host D capsules E metabolic products Answer A 2 Which of the following contributes to the virulence of a pathogen A toxin production B evasion of host defenses C numbers of microorganisms that gain access to a host D numbers of microorganisms that gain access to a host and evasion of host defenses E numbers of microorganisms that gain access to a host evasion of host defenses and toxin production Answer E Table 15 1 Bacterium Portal of Entry Staphylococcus aureus Staphylococcus aureus Wound Wound Ampicillin ID50 10 300 3 Table 15 1 shows the ID50 for Staphylococcus aureus in wounds with and without the administration of ampicillin before surgery Based on the data the administration of ampicillin before surgery A has no effect on risk of infection B increases the risk of staphylococcal infection C replaces tetracycline D decreases the risk of staphylococcal infection E The answer cannot be determined based on the information provided Answer D 4 The fimbriae of Neisseria gonorrhea and enteropathogenic E coli are examples of A receptors B ligands C adhesins D adhesins and ligands E adhesins ligands and receptors Answer D 5 Superantigens produce intense immune responses by stimulating lymphocytes to produce A leukocidins B exotoxins C cytokines D endotoxins E interferons Answer C 1 6 Which of the following is NOT a cytopathic effect of viruses A inclusion bodies forming in the cytoplasm or nucleus B toxin production C increased cell growth D host cells fusing to form multinucleated syncytia E cell death Answer B 7 Nonpathogenic Vibrio cholerae can acquire the cholera toxin gene by A infecting a pathogenic Vibrio cholerae B conjugation C transduction D transformation E phagocytosis Answer C 8 Gram negative septic shock results from the following events What is the second step A IL 1 is released B Body temperature is reset in the hypothalamus C LPS is released from gram negative bacteria D Phagocytes ingest gram negative bacteria E Fever occurs Answer C Table 15 2 ID50 20 1 10 57 Bacterium E coli O157 H7 Legionella pneumophila Shigella Treponema pallidum 9 Which organism in Table 15 2 causes the most severe disease A E coli O157 H7 B Treponema pallidum C Legionella pneumophila D Shigella E It cannot be determined from the information provided Answer E 10 Which of the following statements about M protein is FALSE A It is heat and acid resistant B It is readily digested by phagocytes C It is a protein D It is found on fimbriae E It is found on Streptococcus pyogenes Answer B 2 11 Symptoms of protozoan and helminthic diseases are due to A tissue damage due to growth of the parasite on the tissues B waste products excreted by the parasite C products released from damaged tissues D tissue damage due to growth of the parasite on the tissues and waste products excreted by the parasite E tissue damage due to growth of the parasite on the tissues waste products excreted by the parasite and products released from damaged tissues Answer E 12 Which of the following statements is FALSE A Hemolysins lyse red blood cells B Kinase destroys fibrin clots C Leukocidins destroy neutrophils D Coagulase destroys blood clots E Hyaluronidase breaks down substances between cells Answer D 13 Which of the following statements about staphylococcal enterotoxin is FALSE A It causes diarrhea B It is an exotoxin C It causes vomiting D It is a superantigen E It is produced by Staphylococcus aureus growing in the host s intestines Answer E 14 Polio is transmitted by ingestion of water contaminated with feces containing polio virus What portal of entry does polio virus use A skin only B parenteral only C mucous membranes only D skin and parenteral E skin parenteral and mucous membranes Answer C Table 15 2 ID50 20 1 10 57 Bacterium E coli O157 H7 Legionella pneumophila Shigella Treponema pallidum 15 Which organism in Table 15 2 most easily causes an infection A Legionella pneumophila B Treponema pallidum C E coli O157 H7 D Shigella E The answer cannot be determined based on the information provided Answer A 3 16 Which of the following mechanisms is used by gram negative bacteria to cross the blood brain barrier A inducing endocytosis B producing fimbriae C antigenic variation D producing toxins E inducing TNF Answer E 17 Botulism is caused by ingestion of a proteinaceous exotoxin therefore it can easily be prevented by A boiling food prior to consumption B not eating canned food C administering antibiotics to patients D preventing fecal contamination of food E filtering food Answer A 18 Injectable drugs are tested for endotoxins by A culturing bacteria B filtering out the cells C the Limulus amoebocyte lysate test D looking for turbidity E counting the viable bacteria Answer C 19 Endotoxins in sterile injectable drugs could cause A giant cell formation B infection C nerve damage D septic shock symptoms E no damage because they are sterile Answer D 20 All of the following are methods of avoiding host antibodies EXCEPT A antigenic changes B inducing endocytosis C membrane disrupting toxins D IgA proteases E invasins Answer C 21 Endotoxins are A excreted from the cell B part of the gram negative cell wall C A B toxins D molecules that bind nerve cells E associated with gram positive bacteria Answer B 4 22 Which of the following is NOT a membrane disrupting toxin A streptolysin O B streptolysin S C hemolysin D A B toxin E leukocidin Answer D 23 The ability of some microbes such as Trypanosoma or Giardia to alter their surface molecules and evade destruction by the host s antibodies is called A lysogenic conversion B virulence C antigenic variation D cytocidal effect E cytopathic effect Answer C 24 Cholera toxin polypeptide A binds to surface gangliosides on target cells If the gangliosides were removed A Vibrio would bind to target cells B polypeptide A would enter the cells C polypeptide B would not be able to enter the cells D polypeptide A would bind to target cells E Vibrio would not produce cholera toxin Answer C 25 Cytopathic effects are changes in host cells due to A helminthic infections B viral infections C protozoan infections D fungal infections E bacterial infections Answer B 26 Twenty five people developed symptoms of nausea vomiting and diarrhea three to six hours after