Test Bank for BOC Microbiology 6th Edition Questions and Answers

1. The proper blood-to-broth ratio for blood cultures to reduce the antibacterial effect of serum in adults is: a. 1:2 b. 1:3 c. 1:10 d. 1:30 - Answer-1:10 .2. The most appropriate method for collecting a urine specimen from a patient with an indwelling catheter is: a. remove the catheter, cut the tip, and submit it for culture b. disconnect the catheter from the bag, and aseptically collect urine from the terminal end of the catheter c. aseptically collect urine directly from the drainage bag d. aspirate urine aseptically from the catheter tubing - Answer-aspirate urine aseptically from the catheter tubing .3. Which of the following groups of specimens would be acceptable for anaerobic culture? a. vaginal swab, eye swab b. intraoral surface swab, leg tissue c. pleural fluid, brain abscess fluid d. urine, sputum - Answer-pleural fluid, brain abscess fluid .4. Sodium polyanetholsulfonate (SPS) is used as an anticoagulant for blood cultures because it: a. inactivates penicillin and cephalosporins b. prevents clumping of red cells c. inactivates neutrophils and components of serum complement d. facilitates growth of anaerobes - Answer-inactivates neutrophils and components of serum complement .5. The optimal collection of a wound specimen for culture of anaerobic organisms is a: a. swab of lesion obtained before administration of antibiotics b. swab of lesion obtained after administration of antibiotics c. syringe filled with pus, obtained before administration of antibiotics d. syringe filled with pus, obtained after administration of antibiotics - Answer-syringe filled with pus, obtained before administration of antibiotics .6. The most important variable in the recovery of organisms in adult patients with bacteremia (bacterial sepsis) is: a. subculture of all bottles at day 5 of incubation b. the recommended volume of blood cultured c. collection of daily blood culture sets for 3 consecutive days d. collection of multiple blood culture sets from a single venipuncture - Answer-the recommended volume of blood cultured .7. Virus transport medium should contain agents that: a. enable rapid viral growth during the transport time b. inhibit bacterial and fungal growth c. destroy nonpathogenic viruses d. inhibit complement-fixing antibodies - Answer-inhibit bacterial and fungal growth .8. A bronchoscopy sample with the request for culture of Legionella is sent to the laboratory. The correct plating protocol is: a. culture on thiosulfate citrate bile salt media b. incubate the culture media anaerobically c. reject the specimen and request a sputum sample d. culture on buffered charcoal yeast extract agar with antibiotics - Answer-culture on buffered charcoal yeast extract agar with antibiotics .9. A community hospital microbiology laboratory is processing significant numbers of stool cultures because of an outbreak of diarrhea following heavy rains and flooding in the county. A media that should be incorporated in the plating protocol is: a. colistin nalidixic acid for Listeria b. MacConkey agar with sorbitol for Campylobacter c. mannitol salt agar for Enterococcus species d. thiosulfate citrate bile salts sucrose for Vibrio species - Answer-thiosulfate citrate bile salts sucrose for Vibrio species .10. A male urethral discharge specimen submitted for culture should be inoculated to: a. sheep blood and phenylethyl alcohol agars b. eosin-methylene blue and sheep blood agars c. thioglycollate broth and chocolate agar d. chocolate and modified Thayer-Martin agars - Answer-chocolate and modified Thayer-Martin agars .11. The steam autoclave method of sterilization requires: a. 15 Ib of pressure for 15 minutes b. dry heat for 20 minutes c. a maximum temperature of 100C d. a source of ethylene oxide - Answer-15 Ib of pressure for 15 minutes .12. Which selective medium is used for the isolation of gram-positive microorganisms? a Columbia CNA with 5% sheep blood b trypticase soy agar with 5% sheep blood c eosin methylene blue d modified Thayer-Martin - Answer-Columbia CNA with 5% sheep blood .13. Campylobacter jejuni isolation requires the fecal specimen be: