MICROBIOLOGY EXAM III
SIMPLE COMPLETION:
Each of the questions or incomplete statements in this group is followed by four or five
suggested answers or completions. Select the one which is best in each case and mark the
corresponding letter on the answer sheet:
1. Which of the following is true concerning the orthomyxoviruses?
A. Influenza A, B, and C cause human disease
B. Neuraminidase and hemagglutinin are nuclcocapsid proteins
C. The genome is segmented, composed of eight RNA units
D. The matrix protein is important for vaccine inclusion
E. Dogs are a reservoir of influenza hemagglutinin and neuraminidase subtypes
2. How do point mutations, responsible for antigenic drift, occur in the hemagglutinin and
neuraminidase of the orthomyxoviruses?
A. Gamma rays cause the mutations
B. Poor template copying by the RNA polymerase cause the mutations
C. Genetic reassortment occurs by two cells being coinfected by two different
subtypes of influenza A
D. Prevailing winds "drift" the different naturally occurring mutants throughout the
hemispheres
3. Which of the following statements best describes antigenic shift within the
orthomyxoviruses?
A. A minor antigenic change of the envelope proteins
B. A major antigenic change of the envelope proteins
C. A medium antigenic change of the envelope proteins
D. A minor lipid change of the envelope proteins
E. A major lipid change of the envelope proteins
4. Which one of the following members of the paramyxovirus genus within the
paramyxovirus family is responsible for severe respiratory disease during the summer
time?
A. parainfluenza 1
B. parainfluenza 2
C. parainfluenza 3
D. parainfluenza 4
E. mumps
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5. Measles is a member of the paramyxovirus family, but it differs from mumps and the
parainfluenza viruses structurally with respect to envelope proteins. How do they differ?
A. Measles has a neuraminidase but no hemagglutinin; mumps and parainfluenza
have only hemagglutinin
B. Measles has no hemagglutinin or neuraminidase, mumps and parainfluenza have
only neuraminidase
C. Measles has a neuraminidase but no hemagglutinin; mumps and parainfluenza
have hemagglutinin and neuraminidase
D. Measles has a hemagglutinin but no neuraminidase; mumps and parainfluenza
have hemagglutinin and neuraminidase
6. The syncytial-forming capability that all members of the paramyxovirus family have in
common is a consequence of which of the following viral proteins?
A. hemagglutinin
B. neuraminidase
C. fusion protein
D. polymerase
E. thymidine kinase
7. What is always required for a successful first step in viral infection of an eukaryotic cell?
A. the presence of the correct viral polymerase
B. the presence of the correct virus receptor
C. the presence of a nucleus in the eucaryotic cell
D. the presence of cellular polyribosomes
E. the presence of the correct number of viral genome segments
8. What is one component of all mammalian viruses?
A. the envelope
B. the polymerase
C. the icosahedral capsid
D. the lipid
E. the nucleic acid
9. What is the role of the "early genes" of a mammalian virus?
A. initiation and regulation of virus replication
B. maintenance of the virus outside the cell
C. coding for the structural proteins of the virus
D. determining the group specific antigens of the virus
E. coding for the lipid components of the viral envelope
10. Which of the following host proteins is the first to rise to high titer, in response to viral
infection?
A. Immunoglobulin
B. Complement
C. Interferon
D. Anti-idiotype antibody
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11. What characteristic is shared by the Salk and the Sabin vaccines?
A. Both are attenuated, active vaccines.
B. Both are composed of virus serotypes 1, 2, and 3.
C. Both are administered by injection.
D. Both are capable of reversion to virulence
E. Both are shed in the feces of vaccines.
12. The adenovirus vaccine is administered in order to prevent a specific disease. What disease is
it?
A. adenoidal tumor
B. gastroenteritis
C pneumonia
D. keratinoconjunctivitis
E. rhinitis
13. How can an eye infection by a specific adenovirus be diagnosed?
A. By monitoring the response of the infection to steroid therapy.
B. By using serotype antibody to test inhibition of hemagglutination.
C. By detecting the presence of viral double stranded DNA.
D. By-using electron microscopy to detect viral particles in an eye swab.
E. By detecting nuclear inclusions in infected cells collected in an eye swab.
14. What are the characteristics of Parvoviruses?
A. Small, ssRNA, enveloped viruses
B. Small, ssRNA, naked icosahedral viruses
C. Small, ssDNA, enveloped viruses
D. Small, ssDNA, naked icosahedral viruses
15. A vaccine to prevent Parvovirus B19 infection would prevent what disease?
A. Diarrhea
B. Aplastic crisis
C. Keratoconjunctivitis
D. Pneumonia
E. "Slow" virus disease
16. For which of the following viruses is the presence of heterophile antibody diagnostic?
A. EBV
B. CMV
C. HSV-1
D. HHV7
17. What is the specimen from which herpes simplex virus is most likely to be cultured?
A. saliva
B. spinal fluid
C. vesicle fluid
D. swab from ulcer bed
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18. Which herpesvirus can cause severe E congenital infection?
A. HSV-1
B. VZV
C. EBV
D. CMV
19. What is the reactivation of VZV in an adult called?
A. infectious mononucleosis
B. shingles
C. aphthous stomatitis
D. chronic fatigue syndrome
20. Antibodies to EBNA, EA and VCA are characteristic of infection with:
A. HSV-2
B. CMV
C. EBV
D. VZV
21. The most common cause of fatal, sporadic encephalitis in the United States is:
A: HSV
B. CMV
C. herpes B virus
D. VZV
22. The actinomycetes are:
A. gram-negative branching rods
B. etiologic agents of tinea versicolor
C. often found in sulfur granules
D. sensitive to fluconazole
E. all of the above
23. A 62 year-old diabetic with fever, cough, and bilateral pulmonary infiltrates undergoes
bronchoscopy. Examination of biopsied tissue by the Gomori methenamine silver stain
reveals the presence of nonseptate hyphae, with 90° angle branching. The most likely
etiologic agent is:
A. Aspergillus fumigatus
B. Cryptococcus neoformans
C. Blastomyces dermatitidis
D. Candida albicans
E. Mucor species
24. An important feature for the identification of Candida albicans is:
A. macroscopic observation of black mycelia
B. microscopic observation of a capsule
C. microscopic observation of broad-based budding yeasts
D. pigmentation of colonies on all fungal media
E. germ tube production
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25. Structures associated with the teleomorphic state of a fungus include:
A. ascospores.
B. sporangiospores
C. tuberculate macroconidia
D. conidiophores
E. arthroconidia
26. Microscopic visualization of Cryptococcus neoformans in cerebrospinal fluid is best
accomplished by performing:
A. a lactophenol cotton blue stain
B. a KOH preparation
C. a modified Kinyoun acid-fast stain
D. an India ink examination
E. a Gram stain
27. The antifungal activity of amphotericin B is:
A. inadequate, as a single agent, for the treatment of disseminated
coccidioidomycosis
B. based on the ability to disrupt membrane permeability
C. diminished when combined with 5-fluorocytosine
D. evaded by a cytosine deaminase mutation
28. Sclerotic bodies are often seen in which of the following mycoses:
A. mycetoma
B. sporotrichosis
C. black piedra
D. candidiasis
E. chromomycosis
29. Key morphologic features of the Mucorales include:
A. nonseptate hyphae, presence of sporangia, presence or absence of rhizoids
B. nonseptate hyphae, presence of rhizoids, presence or absence of sporangia
C. septate hyphae, presence of chlamydoconidia, presence or absence of
blastoconidia
D. nonseptate hyphae, presence of macroconidia, presence or absence of asci
E. none of the above
30. Fungal dimorphism is:
A. an essential biological process for reproduction
B. an adaptive biological process in anamorphic growth
C. both A & B
D. neither A nor B
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31. The microscopic morphology of Coccidioides immitis displays:
A. broad-based budding yeast at 37°C
B. arthrospores at 37°C
C. both A & B
D. neither A nor B
32. Which hepatitis viruses are predominantly transmitted by the fecal-oral route?
A. HAV, HBV, HEV
B. HAV, HBV
C. HBV, HCV, HDV
D. HAV, HEV
E. HBV, HDV, HEV
33. Which hepatitis viruses are predominantly transmitted by the parenteral route?
A. HAV, HBV, HEV
B. HAV, HBV
C. HBV, HCV, HDV
D. HAV, HEV
E. HBV, HDV, HEV
34. A patient with acute HBV infection may have the following serologic profile:
A. HBsAg negative, anti-HBs antibody positive, anti-HBc antibody positive
B. HBsAg positive, anti-HBs antibody negative, anti-HBc antibody positive
C. HBsAg positive, anti-HBs antibody positive, anti-HBc antibody positive
D. HBsAg negative, anti-HBs antibody negative, anti-HBc antibody positive
E. HBsAg negative, anti-HBs antibody positive, anti-HBc antibody negative
35. The serological profile following HBV vaccination is:
A. Anti-HBc antibody positive
B. Anti-HBe antibody positive
C. Anti-HBs antibody and anti-HBc antibody positive
D. Anti-HBs antibody positive
E. Anti-HBs antibody positive, anti-HBc antibody positive and anti-HBe antibody
positive
MATCHING:
Choose the best answer. Answers may be used once, more than once, or not at all.
Questions 36-38
A. Coxsackievirus A
B. Coxsackievirus B
C. Enterovirus 72
D. Poliovirus
E. Rhinovirus
36. _____ Infection by these viruses is preventable with a licensed vaccine
37. _____ Hepatitis
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38. _____ Infects oropharynx, but not the intestine because the virus is sensitive to
low pH.
Questions 39-40
A. Rotavirus only
B. Norwalk virus only
C. Both A and B
D. Neither A nor B
39. _____ the major cause of pediatric diarrhea
40. _____ fragmented RNA genome makes this virus capable of genetic reassortment
Ouestions 41-44: Match the phrase to the lettered answer on the right.
Chemotherapeutic agent most often prescribed for treatment of:
41. _____ transfusion-acquired vivax malaria
42. _____ ascariasis
43. _____ giardiasis
A. Mebendazole
B. Flagyl
C. Primaquine
D. Praziquantel
E. None of the above
44. _____ schistosomiasis
Ouestions 45-48
The stage in the life cycle through which infection is transmitted:
45. _____ giardiasis
A. larva
B. trophozoite
C. cyst
D. egg
E. sporozoite
46. _____ cysticercosis
47. _____ enterobiasis
48. _____ taeniasis
Questions 49-50
The procedure that is effective in revealing stages important in making a diagnosis:
49. _____ Naeglaria infection
A. blood smear
B. stool exam
C. serological text
D. liver biopsy
E. none of the above
50. _____ neonatal toxoplasmosis
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PART II - LECTURE EXAM, QUESTIONS 51-150
SIMPLE COMPLETION:
Each of the questions or incomplete statements in this group is followed by four or five
suggested answers or completions. Select the one which is best in each case and mark the
corresponding letter on the answer sheet:
51. Why has there been a re-emergence of Whooping Cough in this, and other, countries?
A. New strains have developed.
B. There has been a change in the antigens of the organism that causes this disease.
C. Some children are not being vaccinated.
D. This organism has, become multi-antibioic resistant.
E. None of the above.
52. Assume that the resistance to antibiotics is caused by increased synthesis of the wild- type
enzyme that synthesizes the mycolic acid wall of M tuberculosis. Which genetic process(es)
could lead to increased expression of this enzyme?
A. An "up mutation," which increases the promoter strength of the gene encoding this
enzyme.
B. A mutation that increases the stability of the enzyme's mRNA, so that
more enzyme can be translated from each mRNA molecule.
C. A mutation that increases the efficiency of the ribosome binding site on the
enzyme's mRNA, so that each mRNA is translated more.
D. A mutation in the enzyme that increases the stability of the enzyme to proteolytic
degradation.
E. All of the above.
53. Which of the following contribute to the appearance of mutations in genes?
A. Chemicals that damage bases.
B. Mistakes made by the DNA polymerase during replication.
C. Movement of transposons around the genome.
D. Formation of deletions in directly repeated DNA sequences.
E. All of the above.
54. Bacteriophage lambda is temperate and integrates into the bacterial chromosome at the
lambda att site by which of the following genetic processes?
A. Nonreciprocal homologous recombination
B. Transposition after infection
C. Site-specific recombination
D. Site-specific oligonucleotide mutagenesis
E. General homologous recombination mediated by the recA pathway
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55. Different species of the Enterobacteraceae can conjugate and attempt to exchange genetic
material. What is the most likely thing that will happen to a 48,000 base-pair E. coli F
plasmid that is transferred into a strain of Salmonella typhimurium?
A. After replication of the single strand that is transfered, the F plasmid DNA will
begin to replicate and establish itself in the recipient strain.
B. After replication of the single strand that is transferred, the F plasmid DNA will
be cut by the Salmonella restriction endonuclease and the F will be degraded.
C. The single-strand E. coli F'-DNA will recombine into the S. typhimurium
P chromosome.
D. After replication of the single strand that is transfered, the F plasmid DNA will
recombine into the S. typhimurium chromosome to form an Hfr (high-frequency
recombinant) strain.
E. All of the above.
56. You would like to design a diagnostic test for the 3 base-pair deletion that causes cystic
fibrosis. What would be a reasonable method and efficient method?
A. Clone the entire CF gene from each patient and determine the DNA sequence of the
cloned gene in each case.
B. Design a bacteriophage luciferase assay that will detect function of the CF gene.
C. Choose two oligonucleotide primers that immediately flank the known CF deletion,
amplify the region by the polymerase chain reaction (PCR), and confirm the presence of
the deletion in the PCR product from each case by electrophoretic methods.
D. Use hybridization methods to isolate the CF mRNA molecule from each patient and
then determine its sequence to confirm the missing bases.
E. Purify and sequence defective CF protein from each patient.
57. Which of the following is true of both Listeria monocytogenes and Bacillus cereus?
A. The organism can penetrate the host cells of the epithelial lining.
B. Infection is primarily found in immunocompromised patients.
C. Infection can often be traced to contaminated food.
D. The organism produces an enterotoxin.
58. Organisms capable of producing endospores include:
A. Clostridium species
B. Escherichia species
C. Bacillus species
D. A and C
E. A, B, and C
59. In which of the following is chronic carriage important to the epidemiology of infection?
A. Legionella pneumophila
B. Shigella flexneri
C. Salmonella typhi
D. Vibrio vulnificus
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60. Which of the following is a common cause of Francisella tularensis infection?
A. Contaminated water
B. Heating/Cooling systems
C. Tick Bites
D. Sharing contaminated needles
E.Stress
61. Which of the following does not contribute to the difficulty of diagnosing Francisella
tularensis infections? That is, which facilitates diagnosing F. tularensis infections?
A. Gram stains of sputum usually do not reveal the presence of the organism.
B. Antibodies crossreact with Brucella.
C. The organism swarms when inoculated on cysteine-glucose-blood agar plates.
D. Aerosolization during culturing represents a potential source of infection for
laboratory workers.
62. An employee of a meat-packing plant complains of fever, weakness, weight loss, and
headaches lasting over a prolonged period of several weeks. Using your knowledge of
occupation-related diseases, you order serological tests to determine if your patient is infected
with:
A. Mycobacterium tuberculosis
B. Brucella
C. Legionella
D. Vibrio cholerae
E. Yersinia
63. Chronic Brucellosis is:
A. Characterized by low grade fever, joint pains, and other vague complaints for several
years.
B. A well-characterized illness involving the formation of draining abscesses.
C. Diagnosed by inoculation of sputum or exudates on cysteine-glucose-blood agar.
D. Acquired by tick or deer fly bites.
64. The pathological hallmark of Legionnaire's disease is:
A. Abscess formation and petechial skin lesions
B. Macular-papular rash on the trunk
C. Acute meningococcemia
D. An infra-alveolar exudate of leukocytes and macrophages
65. Diagnosis of a Neisseria infection in women relies on:
A. Gram stain of mucosal sites.
B. Catalase test.
C. Culture on Thayer-Martin media.
D. Culure on cysteine-blood-glucose media.
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66. For Neisseria, generation of variant pilin forms naturally occurs by:
A. Intragenic recombination.
B. Extragenic recombination.
C. Transformation.
D. Transduction.
67. The human host has difficulty producing humoral antibodies that are effective against certain
antigenic determinants of Neisseria. This is due to the organism's property of:
A. Minicell formation.
B. Antigenic variation.
C. Excessive polysaccharide production.
D. Synthesis of penicillin-binding proteins.
68. For Neisseria meningitidis, the serogroup most often associated with epidemics is:
A. A
B. B
C. Y
D. W135
69. Host immunity to Neisseria meningitidis infection is:
A. Not affected by blocking IgA antibody.
B. Mediated by cell-mediated-immunity.
C. Mediated primarily by bacteriocidal antibodies.
D. Not possible.
Questions 70-72: Which of the following choices makes the statement UNTRUE?
70. During the course of disease due to a normal Vibrio cholerae infection the patients will
likely:
A. show signs of disease at 8 to 72 hrs after ingestion of contaminated food or
water.
B. sustain considerable damage to their intestines.
C. experience nausea, vomiting, abdominal cramping, and diarrhea.
D. sometimes lose between 10 to 20 liters of fluid/day.
71. To prevent Vibrio parahaemolyticus infections, one should:
A. cook seafood for the appropriate time
B. never return cooked seafood to the original container
C. consume alcohol along with raw seafood
72. The bacterium classified as Vibrio cholerae O antigen group 1 (V. cholerae 01):
A. invades the small intestine
B. is often associated with marine environments
C. causes disease only through the production of an enterotoxin
D. Reacts with group 1 antiserum against the lipopolysaccharide (0) antigens
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73. Which of following completions makes the statement TRUE?
Only recently have Campylobacter . and Helicobacter been identified as the causative
agents for certain infections. This is because the clinical laboratories now routinely test
for organisms with the following characteristic:
A. inability to ferment carbohydrates
B. single polar flagellum
C. microaerophilic nature
D. small size
74. Which of following completions makes the statement TRUE?
Almost all persons infected with Helicobacter pylori will:
A. eventually develop either peptic ulcers or gastric cancer
B. suffer no clinical manifestations of the infection
C. develop severe diarrhea
D. develop bacteremia
75. The beta-lactamase of Staphylococcus aureus inactivates which of the following?
A. Oxacillin
B. Methicillin
C. Ampicillin
D. Vancomycin
76. Which ones are narrow spectrum drugs?
A. Vancomycin and Cephalosporins
B. Cephalosporins and Aztreonam
C. Aztreonam and Vancomycin
D. Tetracycline and Vancomycin
77. The laboratory calls to alert you that a patient, who has been in the intensive care unit of the
hospital for a long period of time, has several blood cultures with Gram Positive cocci in
clusters. You suspect the diagnosis to be line related sepsis due to which organism?
("Line related sepsis" is sepsis related to the presence of an IV tube or line, for example.):
A. Group A streptococcus
B. Clostridium difficle
C. Staphylococcus sp. not S. aureus
D. Viridans streptococci
78. Lyme disease:
A. is most commonly found in the central United States.
B. is transmitted by lice.
C. is caused by Leptospira interrogans.
D. is most prevalent in forested areas with high deer populations.
E. is caused by an obligate parasite of humans.
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79. Which of the following organisms is transmitted directly by human to human contact?
A. Borrelia hermsii
B. Treponema pallidum subspecies pallidum
C. Leptospira interrogans
D. Spirillum minor
E. Borrelia burgdorferi
80. The antigenic changes occurring during relapsing fever:
A. result from the switching of unexpressed Variable Major Protein (VMP) genes into an
expression site.
B. do not affect the course of the disease.
C. result in multiple relapses involving organisms with the exact same VMP protein.
D. result from changes at the transcriptional level (not genotypic changes).
81. Manifestations of tertiary (late) syphilis can include all of the following EXCEPT:
A. aortic aneurism.
B. multiple skin lesions containing numerous organisms.
C. infection of the brain.
D. formation of granulomatous lesions anywhere in the body.
E. loss of sensory and motor function in the lower extremities.
82. Features that Borrelia burgdorferi and Treponema pallidum subsp. pallidum have in common
include:
A. mode of transmission.
B. arthritis as a late manifestation.
C. local, disseminated, and chronic (persistent) stages of infection.
D. ease of in vitro culture in artificial medium.
E. diagnosis of infection through detection of anticardiolipin antibodies.
83. Which one is a risk factor for tuberculosis?
A. middle aged adult
B. Scandinavian
C. alcoholism
D. stockbroker
E. female
84. The single most reliable procedure for the diagnosis of genitourinary tuberculosis is:
A. acid-fast stain
B. PPD skin test
C. culture of urine
D. chest X-ray
E. histology of a biopsy
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85. Which one of the following statements is untrue?
Droplet nuclei:
A. are the chief means of transmitting pulmonary infection with tuberculosis
B. are usually produced by coughing or sneezing
C. may float in air for several hours
D. are not an important source of tuberculosis infections acquired in the emergency
centers city/county hospitals
E. become small enough to bypass the normal upper airway defenses
86. Which of the following is untrue of Nocardia?
A. It is acid fast.
B. It is gram positive.
C. It grows well in compost.
D. It may cause disseminated infection.
E. It requires a medium supplemented with blood.
87. The most common source of infection for Mycobacterium tuberculosis in the U.S. is:
A. sputum
B. urine
C. wound
D. milk
E. soil
88. Those with AIDS (Acquired Immunodeficiency Syndrome) are most likely to have a severe
infection with which one of the following organisms?
A. Actinomyces israelii
B. Mycobacterium marinum
C. Mycobacterium avium-intracellulare
D. Mycobacterium smegmatis
E. Nocardia asteroides
89. All but one statement is true of Mycobacterium tuberculosis; which one is untrue?
A. obligate aerobe
B. produces few if any toxins
C. grows rapidly
D. requires an enriched medium
E. Niacin positive
90. Assuming a positive skin test, who has the highest risk for illness with M tuberculosis?
A. A 6-year-old child whose father has pulmonary TB that was diagnosed six months
ago.
B. Males over 45.
C. Abnormal chest X-ray.
D. A patient treated for 9 months with INH and Rifampin.
E. A 40-year-old male with a partial gastrectomy.
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91. Which of the following statements is untrue?
The tuberculin skin test:
A. is positive at 15 mm in duration or greater
B. may be falsely negative in severely immunocompromised patients
C. may be falsely positive in those with hepatitis
D. is positive in about six weeks after becoming infected with the organism
E. is done with a purified protein derivative (PPD) of killed organisms
92. Which of the following organisms has the lowest infective dose?
A. Enterotoxigenic Escherichia coli
B. Enteroinvasive E. coli
C. Salmonella enteriditis
D. Shigella flexneri
93. Some of the pathogenic members of the family Enterobacteriaceae require a small number of
cells to infect and then produce disease. The reason for this is:
A. Nutrient requirements of the different organisms
B. Greater ability to survive an acid environment
C. There are more species present in nature than the less infective organisms
D. These bacteria produce more flagella than other members of this family
94. Which of the following diarrheagenic Escherichia coli have been associated with the
sequella called Hemolytic Uremic Syndrome?
A. Enterotoxigenic Escherichia coli
B. Enteroinvasive E. coli
C. Enteropathogenic E. coli
D. Enterohemorrhagic E. coli
95. Which of the following organisms are zoonotic (animal-to-man) infections in humans?
A. Yersinia pestis
B. Shigella flexneri
C. Enterotoxigenic Escherichia coli
D. Chlamydia trachomatis
96. Sporadic cases of bubonic plague most commonly occur when humans come in contact with
the:
A. American cycle
B. European cycle
C. Bi cycle
D. Urban cycle
E. Sylvatic cycle
97. Which of the following are not true about Shigella?
A. Serotyping based on O and H antigens
B. Causes bacillary dysentery
C. Most strains are lactose nonfermenters
D. Virulence is plasmid mediated
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98. Which characteristic does not belong to the Family Enterobacteriaceae?
A. glucose fermentation
B. motility
C. gram negative bacilli
D. cytochrome oxidase positive
E. reduces nitrates to nitrites
99. Which of the following members of the Enterobacteriaceae is the most common cause of
urinary tract infections?
A. Klebsiella pneumoniae
B. Salmonella typhi
C. Escherichia coli
D. Shigella sonnei
100. The hallmark of therapy for severe cases of cholera is:
A. antimicrobial therapy
B. vaccination
C. replacement of electrolytes
D. outpatient treatment
101. What is the most prominent virulence characteristic of Klebsiella pneumoniae
A. invasion
B. capsule
C. abscess formation
D. toxin production
102. Sources of human Salmonella infection can be:
A. Poultry products
B. Turtles
C. Sewage contaminated food and water
D. All of the above
E. None of the above
103. Infection with which organism is most likely to result in septicemia?
A. EIEC
B. Shigella flexnerii
C. Salmonella enteriditis
D. EAggEC
104. Chlamydia pneumonia is the etiological agent of:
A. Inclusion conjunctivitis
B. Lymphogranuloma venereum
C. Hyperendemic, blinding trachoma
D. All of the above
E. None of the above
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105. The infectious stage of the chiamydial life cycle is the:
A. Exocytic particle
B. Lysosome
C. Elementary body
D. Reticulate body
E. Cytoadsorption body
106. Microscopic examination of clinical specimens from patients with suspected chiamydial
infections is effective only in:
A. Ornithosis
B. Lymphogranuloma venereum
C. Primary Atypical Pneumonia
D. Urethritis
E. None of the above
107. The organism which produces the most common, sexually transmitted disease in the United
States is:
A. Treponema pallidum
B. Neisseria gonorrhoeae
C. Ureplasma urealyticum
D. Chlamydia trachomatis.
E. Chlamydia psittaci
108. Which of the following is true about Chlamydia and separates them from Rickettsia?
A. Chlamydia can be grown on artificial media
B. Chlamydia synthesize their own ATP
C. Chlamydia have a unique developmental cycle
D. Chlamydia contain cytochromes
109. A child comes to your office with a headache, malaise, mild fever, and a rash developing on
the trunk of the body. The mother tells you that the family recently returned from South
America, where each member had picked up a body louse infestation. A possible cause of
this disease is:
A. Enteroinvasive Escherichia coli
B. Mycobacterium smegmatis
C. Pseudomonas aeruginosa
D. Rickettsia rickettsii
E. Rickettsia prowazekii
110. The most common type of Haemophilus influenzae that produces disease in humans:
A. type a
B. type b
C. type c
D. type d
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111. A major virulence factor of Haemophilus influenzae is:
A. LPS
B. Outer membrane proteins
C. Pili
D. Capsule
E. None of the above
MATCHING:
Choose the BEST answer. Answers may be used once, more than once, or not at all.
Questions 112-115
A. Causes PAP
B. Rash first appears on the extremities and is transmitted by ticks
C. Is resistant to extreme environmental conditions
D. Penicillin is the drug of choice
E. Transmitted by the rat flea
112. _____ Rickettsia rickettsii
113. _____ Coxiella burnetii
114. _____ Mycoplasma pneumoniae
115. _____ Rickettsia akari
Questions 116-119
Match each of the following organisms with the appropriate mechanism of transmission.
A. food
B. insect vector
116. _____Vibrio cholerae
117. _____Rickettsia prowazekii
118. _____ Rochalimaea quintana
119. _____ A Listeria monocytogenes
- 18 -
Questions 120-123
Match the organism with its usual colonizing site (each answer is used once
I
A. Bacteroides melanogenicus
B. Coagulase negative Staphylococcus
C. Lactobacillus spp
D. Streptococcus faecalis
120. _____ Intestine
121. _____ Skin
122. _____ Vagina
123. _____ Mouth
Questions 124-125
A. Enzymatic cleavage of the antibiotic
B. Mutation to ribosomal resistance
C. Enzymatic modification of an antibiotic by adding hydroxy amino groups but
without cleaving the molecule
D. Plasmid mediated efflux pump
124. _____ Beta-lactamase
125. _____ Non-plasmid mediated high-level streptomycin resistance
Questions 126-127
Match the following mechanisms with the best choice of antibiotic.
A. Aminoglycosides (or tetracyclines, erythromycin, clindamycin)
B. Fluoroquinolones (e.g., ciprofloxacin)
C. Rifampin
D. Sulfonamides or trimethoprim
126. _____ Interference with folic acid synthesis
127. _____ Interference with DNA dependent RNA synthesis
- 19 -
Questions 128-130
Match the organism with the primary laboratory method used for its identification.
A. Camp test
B. Bile esculin and salt tolerance
C. Coagulase
D. Optochin susceptibility ("p" disk)
128. _____ Staphylococcus sp. not S. aureus
129. _____ Enterococcus species
130. _____ Streptococcus pneumoniae
Questions 131-132
Each group of questions below consists of five lettered headings followed by a list of numbered
words or statements. For each numbered word or statement, select the one lettered heading that is
most closely associated with it. Each lettered heading may be selected once, more than once, or
not at all.
A. Negative growth rate of bacteria
B. Zero growth rate of bacteria
C. Decreasing growth rate of bacteria
D. Constant growth rate of bacteria
E. increasing growth - rate of bacteria
131. _____ During exponential phase
132. _____ During maximum stationary phase
Questions 133-136
A. Obligate anaerobe.
B. Obligate (strict) aerobe
C. Microaerophile
D. Facultative organism
133. _____ Bacteria that make either fermentative or a respiratory set of enzymes
134. _____ Organisms that can use only molecular oxygen as the final acceptor
135. _____ Escherichia, Salmonella, and Shigella species
136. _____ Treponema species
- 20 -
TRUE OR FALSE:
Choose the best possible answer. A = True; B = False
137. _____ Lymphogranuloma venereum is more common in upper socioeconomic
conditions than in lower socioeconomic conditions.
138. _____ Human infections with Chlamydia psittaci are almost never fatal and are
usually inapparent or mild.
139. _____ Pseudomonas aeruginosa infections are common in uncompromised, otherwise
healthy humans.
140. _____ Berdetella pertusis can be isolated throughout the course of the infection.
141. _____ Bacteroides fragilis is sensitive to penicillin G.
142. _____ Fusobacterium have the appearance of "fused" safety pins on Gram stain.
143. _____Expectorated sputum is an unacceptable specimen for anaerobic culture.
144. _____ Clostridium perfringens produces a hemolysin that clinically may cause
breakdown of red blood cells and severe anemia (hemolytic anemia) in
the infected human.
145. _____ Anaerobes can often be categorized in the research laboratory by the long
chain fatty acids they produce.
146. _____ In gas gangrene caused by Clostridium perfringens, the gas may not be
apparent on exam or x-ray.
147._____ Clostridium perfringens often produces characteristic spores in clinical
specimens.
148. _____ Vancomycin is inactive against anaerobes.
149. _____ Kanamycin is inactive against anaerobes.
150. _____ A candle jar, once the flame is extinguished by consumption of 02, is a
useful and cheap environment for the growth and isolation of anaerobes.
- 21 -
ANSWERS:
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
C
B
B
C
D
C
B
E
A
C
B
C
B
D
B
A
C
D
B
C
A
C
E
E
D
D
B
E
A
B
D
D
C
B
D
D
C
E
A
A
E
A
B
D
C
D
D
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
61.
62.
63.
64.
65.
66.
67.
68.
69.
70.
71.
72.
73.
74.
75.
76.
77.
78.
79.
80.
81.
82.
83.
84.
85.
86.
87.
88.
89.
90.
91.
92.
93.
94.
A
E
C
B
C
E
C
B
C
C
D
C
C
C
B
A
D
C
A
B
A
C
B
C
A
C
B
C
C
C
D
B
A
B
C
C
C
D
E
A
C
C
A
C
D
B
D
95.
96.
97.
98.
99.
100.
101.
102.
103.
104.
105.
106.
107.
108.
109.
110.
111.
112.
113.
114.
115.
116.
117.
118.
119.
120.
121.
122.
123.
124.
125.
126.
127.
128.
129.
130.
131.
132.
133.
134.
135.
136.
137.
138.
139.
140.
141.
- 22 -
A
E
A
D
C
C
B
D
C
E
C
E
D
C
E
B
D
B
C
A
E
A
B
B
A
D
B
C
A
A
B
D
C
C
B
D
D
B
D
B
D
A
B
A
B
B
B
142.
143.
144.
145.
146.
147.
148.
149.
150.
B
A
A
B
A
B
B
A
B