SP2 - MICROBIO Flashcards
Substrate used in Kovac’s indole test:
a. Indole
b. Tryptophan
c. Para-dimethylaminobenzaldehyde
d. Para-dimethylaminocinnamaldehyde
Tryptophan
Indole test differentiates which set of
organisms?
a. Morganella and Providencia
b. Salmonella and Shigella
c. P. vulgaris and P. mirabilis
d. E. coli and Klebsiella oxytoca
c. P. vulgaris and P. mirabilis
Inhibitors for gram (+) bacteria on MAC:
a. Crystal violet and vancomycin
b. Colistin and anisomycin
c. Trimethoprim and vancomycin
d. Bile salts and crystal violet
Bile salts and crystal violet
Colonies of Salmonella on SSA:
a. Colorless colonies with black
center
b. Colorless colonies without black center
c. Red colonies with black center
d. Red colonies without black center
Colorless colonies with black
center
Which of the following is a correct pair?
a. S. aureus – pink colonies on MSA
b. K. pneumoniae – colorless colonies on
MAC
c. S. pneumoniae – non-hemolytic on SBA
d. E. coli – yellow colonies on XLD
E. coli – yellow colonies on XLD
All members of Enterobacteriaceae are motile at 37degC except:
- Klebsiella
- Proteus
- Shigella
- Yersinia
a. 1, 2, and 3
b. 1, 3, and 4
c. 1 and 3
d. 1 and 4
1, 3, and 4
(Proteus is the only motile enterobacteriaceae)
pH indicator of LIA:
a. Neutral red
b. Phenol red
c. Bromothymol blue
d. Bromcresol purple
Bromcresol purple
Yellow butt and red slant in TSI tube indicates fermentation of:
a. Lactose
b. Glucose
c. Lactose and glucose
d. Lactose and/or sucrose
Glucose
Heat stable antigen of enterics located on their cell wall:
a. O
b. K
c. H
d. Vi
O
ONPG test allows organism to be classified as lactose fermenter by testing which of the following:
a. B-lactamase
b. B-galactosidase
c. Lactose permease
d. Tryptophanase
B-galactosidase
Only oxidase positive member of Enterobacteriaceae:
a. Shigella
b. Morganella
c. Plesiomonas
d. Edwardsiella
Plesiomonas
V. cholerae colonies on TCBS:
a. Blue
b. Green
c. Yellow
d. Red
Yellow
Which of the following sets of results represents the most common reactions for Moraxella catarrhalis when tested in CTA sugar tubes?
a. Glucose (-); Maltose (-); Lactose
(-); Sucrose (-)
b. Glucose (+); Maltose (-); Lactose (-);
Sucrose (-)
c. Glucose (+); Maltose (+); Lactose (-);
Sucrose (-)
d. Glucose (+); Maltose (-); Lactose (+);
Sucrose (-)
Glucose (-); Maltose (-); Lactose
(-); Sucrose (-)
(Moraxella catarrhalis is asaccharolytic)
Neisseria lactamica can be differentiated from N. meningitidis through which of the following?
a. Colony morphology
b. Use of selective media
c. Glucose and maltose utilization
d. ONPG test
ONPG test
Isolates of the suspected C. diphtheriae must be tested for in vitro production of exotoxin thru:
a. Anton test
b. Elek test
c. Frei test
d. Mantoux test
Elek test
Lecithinase production, double zone hemolysis on SBA, and gram-stain morphology are all useful criteria in the identification of which of the following?
a. C. perfringens
b. S. agalactiae
c. E. coli
d. C. tetani
C. perfringens
Sensitivity test result of Group A Streptococci to Bacitracin and SXT respectively:
a. Susceptible and resistant
b. Resistant and susceptible
c. Both susceptible
d. Both resistant
Susceptible and resistant
Correct about gram-positive bacteria:
a. Has thinner peptidoglycan compared to gram-negative
b. Cell wall has an outer layer which
contains lipopolysaccharide
c. Takes up the crystal violet-iodine
complex but is easily decolorized
d. Uses selective isolation media like
colistin-nalidixic acid agar
Uses selective isolation media like
colistin-nalidixic acid agar
Responsible for dark / non-fluorescent
background in Auramine Rhodamine stain for acid-fast bacilli
a. Auramine
b. Rhodamine
c. Potassium permanganate
d. acid-alcohol
Potassium permanganate
Stain for endospore:
a. Wayson
b. Leifson
c. Schaeffer-Fulton
d. Loeffler’s alkaline methylene blue
Schaeffer-Fulton
Most common gas for sterilization:
a. Nitrogen dioxide
b. Chlorine dioxide
c. Ethylene oxide
d. Chlorhexidine gluconate
Ethylene oxide
HEPA filter size used in laboratory hoods and isolation room:
a. 0.3 um
b. 0.6 um
c. 0.9 um
d. 1.2 um
0.3 um
Incorrect about autoclaving:
a. Biologic indicator: B. stearothermophilus
b. Can destroy all forms of microbial life
including spores
c. Dry heat sterilization
d. 121degC / 15 psi / 15 mins
Dry heat sterilization
Uses a strip with varying conc. of antibiotic along its length and MIC can be obtained:
a. Kirby Bauer
b. Microplate dilution
c. Vitek System
d. E test
E test
0.5 MacFarland standard provides an optical density comparable to density of a bacterial suspension of:
a. 0.5 x 10^8 CFU/mL
b. 1.5 x 10^8 CFU/mL
c. 0.5 x 10^9 CFU/mL
d. 1.5 x 10^9 CFU/mL
1.5 x 10^8 CFU/mL
In disk diffusion testing, a delay of more than 15 mins between placing the disks on an inoculated plate and incubation results to:
a. Failure of antibiotic to diffuse in media
b. Zones of smaller diameter will result
c. Zones of larger diameter will
result
d. No effect on final zone diameter
Zones of larger diameter will
result
The term “palisading”, “picket fence”, and“Chinese letter” describe the common arrangement of cells of:
a. Corynebacterium spp
b. Mycobacterium tuberculosis but not the other mycobacteria
c. Actinomyces but not Nocardia
d. Corynebacterium diphtheriae but not
other corynebacteria
Corynebacterium spp
The exchange of cellular DNA between two living bacterial cells that involves an intercellular bridge is which of the following processes?
a. Transformation
b. Transduction
c. Plasmidization
d. Conjugation
Conjugation
The slide coagulase test is a rapid screening test for the production of which of the following:
a. Clumping factor
b. Free coagulase
c. Extracellular coagulase
d. Catalase
Clumping factor
The bacterial species that can be described as susceptible to bile and optochin, a-hemolytic, a major cause of bacterial meningitis, and often carrying an antiphagocytic capsule is which of the following?
a. Enterococcus faecalis
b. S. pneumoniae
c. S. pyogenes
d. S. agalactiae
S. pneumoniae
Which of the following sets of tests provides the best differentiation of L. monocytogenes and E. rhusiopathiae?
a. Gram-stained smear, oxidase, optochin
b. Gram-stained smear, catalase, motility
c. CAMP test, H2S production, esculin hydrolysis
d. Reverse CAMP, gram-stained smear, b-hemolysis
CAMP test, H2S production, esculin hydrolysis
Micrococcus and Staphylococcus species are differentiated by which test(s)?
- O-F tube
- Gram stain
- Catalase test
- Lysostaphin susceptibility
a. 1 and 3
b. 2 and 3
c. 1 and 2
d. 1 and 4
1 and 4
In the test for urease production, the presence of the enzyme hydrolyzes urea to which of the following?
a. Ammonia and CO2
b. Putrescine
c. Amines and CO2
d. Amines and water
Ammonia and CO2
All of the following are correct regarding methylene blue except
a. Inhibits gram-positive bacteria in enteric media
b. Can be used as simple bacterial stain
c. Indicator of anaerobiosis
d. pH indicator in TCBS
pH indicator in TCBS
(pH indicator for TCBS is bromthymol blue)
LOA reaction of Klebsiella pneumoniae:
a. + - -
b. + + -
c. - + -
d. + - +
+ - -
All are correct regarding S. saprophyticus except:
a. Coagulase negative
b. Causes UTI in young women
c. Novobiocin sensitive
d. DNase negative
Novobiocin sensitive
(S. saprophyticus is novobiocin resistant)
Chocolate agar-based medium containing vancomycin, colistin, anisomycin, and trimethoprim is known as:
a. Thayer-Martin
b. Modified Thayer Martin
c. Martin-Lewis
d. New York City
Martin-Lewis
Which of the following is a wrong pair?
a. Brucella abortus – Bang’s bacillus
b. N. meningitidis – Meningococcus
c. H. influenzae – Koch Week’s
bacillus
d. M. avium intracellulare – Battery
bacillus
H. influenzae – Koch Week’s
bacillus
(H. influenzae is Pfeiffer’s Bacillus)
(H. aegypticus is Koch Week’s Bacillus)
Positive result for DNase test:
a. Green
b. Pink
c. Clearing of medium
d. hemolysis
Clearing of medium
Biosafety cabinet where 30% is recirculated air and 70% is exhausted air outside of facility
a. Type II - A1
b. Type II - A2
c. Type II - B1
d. Type II - B2
Type II - B1