Microbiology Flashcards
Which of the following set of organisms should be used to perform QC on the novobiocin disk test?
Staph aureus and staph sapro
Which of the following presumptive identifications correlate with the results below?
PPD green
Urea pink mTSI K/A H2S
a. Morganella
b. Proteus
c. Salmonella
d. Providencia
B
Which of the following tests can be used for organism identification given these findings?
Gram stain gram positive cocci
Blood agar small grey hemolytic
MAC no growth
Catalase negative negative
A. Coagulase, PYR
B. Spot indole, oxidase
C. Latex agglutination, hippurate
D. Optochin, bacitracin
C
Which of the following tests will rapidly differentiate micrococci from staphylococci?
A. Catalase
B. Coagulase
C. Modified oxidase
D. Novobiocin susceptibility
C
The ONPG test allows organisms to be classified as LF by testing for which of the following?
A. Phosphatase
B. Beta-lactamase
C. Beta-galactosidase
D. Oxidase
C
After primer design, what reagent component of a PCR reaction is most important for determining amplification specificity?
A. Taq DNA polymerase
B. Magnesium
C. Extension time
D. Annealing temperature
B
Cycloserine-cefoxitin-fructose agar is used for the recovery of:
A. Yersinia enterocolitica
B. Yersinia intermedia
C. Clostridium difficile
D. Clostridium perfringes
C
By which method are enterococcus spp. and group D non-enterococci best differentiated?
A. Bacitracin susceptibility
B. Porphyrin
C. Bile esculin agar
D. Growth in 6.5% NaCl
D
On what organism is beta-lactamase testing frequently performed?
Haemophilus influenzae
What does the TSI agar contain to allow us to detect H2S? What does it produce H2S from?
Ferrous sulfate and sodium thiosulfate
Is fermentation and aerobic or anaerobic process?
Anaerobic - this is why only the butt will turn yellow in TSI reaction unless it diffuses to the rest of the media
What is found in TSI agar?
Glucose 0.1%
Lactose 1%
Sucrose 1%
What is the incubation conditions for enterobacterales?
Facultative anaerobes
What are the common characteristics of enterobacterales?
Ferment glucose
Reduce nitrate to nitrites
Oxidase negative
What are the only organisms of the enterobacterals that are not motile?
Klebsiella
Shigella
Yersinia
