Medical Microbiology Test Bank 1 Answer Key

Medical Microbiology test bank -1 (Chapter 1-6) 1. These substances include toxins and tissue-damaging enzymes: a. Adhesins. b. Aggressions. c. Impedin. d. Invasions. 2. The most important pathogenicity factors of Enterobacteriaceae are as below except: a. Colonizing factors. b. Endotoxin. c. Invasions. d. Sepsis. 3. These microorganisms are nonpathogenic; their natural habitat is dead organic compounds: a. Commensals. b. Parasites. c. Pathogenicity. d. Saprophytes. 4. Invasion of a host organism by microorganisms, proliferation of the invading organisms, and host reaction a. Colonization. b. Contamination. c. Infection. d. Sepsis. 5. Community of microbes that live in and on an individual; can vary substantially between environmental sites and host niches in health and disease a. Microbiota. b. Microbiome. c. Prebiotic. d. Probiotic. 6. Aggregate collection of microbial genomes in normal microbial flora. a. Microbiota. b. Microbiome. c. Prebiotic. d. Probiotic. 7. Unicellular or metazoan organism living in or on an organism of another species (host) on the expense of the host a. Commensals. b. Parasites. c. Pathogenicity. d. Saprophytes. 8. Normal inhabitants of skin and mucosa; the normal flora is thus the total commensal population. a. Commensals. b. Parasites. c. Pathogenicity. d. Saprophytes. 9. The postulates can be freely formulated as follows except: a. The microorganism must be found under conditions corresponding to the pathological changes. b. It must be possible to cause an identical disease with pure cultures of the pathogen. c. The pathogen must not occur within the framework of other diseases as an “accidental parasite.” d. The pathogen must occur within the framework of other diseases as an “accidental parasite.” 10. Sum of the disease-causing properties of a strain of a pathogenic species. a. Incubation period. b. Infection spectrum. c. Minimum infective dose. d. Virulence. 11. Time between infection and manifestation of disease symptoms; this specific disease characteristic can be measured in hours, days, weeks, or even years. a. Incubation period. b. Infection spectrum. c. Minimum infective dose. d. Mode of infection. 12. Smallest number of pathogens sufficient to cause an infection. a. Incubation period. b. Infection spectrum. c. Minimum infective dose. d. Mode of infection. 13. Pathway used by pathogen to invade host. a. Incubation period. b. Infection spectrum. c. Minimum infective dose. d. Mode of infection. 14. Infection arising from the colonizing flora. a. Endogenous infection. b. Exogenous infection. c. Local infection. d. Nosocomial infection. 15. Infection arising from invasion of host by microorganisms from sources external to it. a. Endogenous infection. b. Exogenous infection. c. Local infection. d. Nosocomial infection. 16. Infections acquired during hospitalization such as urinary tract infections, infections of the respiratory organs, wound infection, sepsis. a. Endogenous infection. b. Exogenous infection. c. Local infection. d. Nosocomial infection. 17. Infection that remains restricted to the portal of entry and surrounding area. a. Endogenous infection. b. Exogenous infection. c. Local infection. d. Nosocomial infection. 18. Gram-negative, oxidase-negative, non–lactose-fermenting motile bacteria are isolated from the urine of a woman with dysuria and frequency. Which bacterium is causing this disease? a. Escherichia coli b. Enterobacter aerogenes c. Proteus mirabilis d. Pseudomonas aeruginosa 19. How is bubonic plague transmitted? a. Faecal-oral route b. On fomites c. Sexual contact d. Zoonotic 20. Which of the following gram-negative, oxidase-negative bacilli isolated from the stool of a person with diarrhoea would yield a colorless colony on MacConkey agar? a. Enterobacter aerogenes b. Escherichia coli c. Klebsiella pneumoniae d. Salmonella typhimurium 21. The virulence factor associated with enterohemorrhagic E. coli diarrhea resembles a virulence factor from which of the following bacteria? a. Enterobacter aerogenes b. Klebsiella pneumoniae c. Salmonella typhi d. Shigella dysenteriae 22. MacConkey-Sorbitol agar is useful for detecting which organism? a. Escherichia coli b. Shigella sonnei c. Salmonella enteric d. Vibrio cholerae 23. This group of gram-negative bacteria contains agents of important diseases such as gastroenteritis and enteric fevers, urinary tract infections, and bacterial pneumonia. a. Neisseriaceae b. Micrococcaceae c. Vibrionaceae d. Enterobacteriaceae 24. Which bacterial family is best described as catalase-positive, oxidase-negative, gramnegative bacilli that are facultative anaerobes and reduce nitrates to nitrites? a. Enterobacteriaceae b. Pasteurellaceae c. Pseudomonadaceae d. Vibrionaceae 25. A sexually active 27-year-old man complains of a greenish-yellow discharge from his urethra and difficulty urinating. Gram-negative diplococci were seen on the Gram stain. Confirmation by culture requires plating on which of the following media? a. Buffered charcoal yeast extract agar b. Middlebrook agar c. Mannitol salts agar d. Thayer-Martin agar 26. Collection and handling of specimens for the detection of Neisseria gonorrhoeae should optimally include which of the following? a. Charcoal-treated nontoxic swabs b. Immediate inoculation to appropriate medium c. CO2-enriched atmosphere d. All of the above 27. Which genus is best described as oxidase-positive, gram-negative cocci that are normal flora of the respiratory and other mucosal surfaces and often form diplococci? a. Haemophilus b. Stomatococcus c. Neisseria d. Staphylococcus 28. Which of the following laboratory characteristics distinguish Enterococcus from Streptococcus? a. Catalase b. Coagulase c. Optochin sensitivity d. Sensitivity to bile 29. Which bacterial species can be described as able to grow in 6.5% NaCl and 40% bile, part of the normal faecal flora of animals and humans, usually nonhemolytic, and a major cause of nosocomial infections? a. Enterococcus faecalis b. Streptococcus pneumoniae c. Streptococcus pyogenes d. Streptococcus agalactiae 30. Which genus is best described as catalase-negative, gram-positive cocci that are facultative anaerobes and form chains? a. Streptococcus