Microbio Flashcards
Substrate used in Kovacs Indole Test A. Indole
B. Tryptophan
C. Para-dimethylaminobenzaldehyde
D. Para-dimethylaminocinnamaldehyde
B. Tryptophan
Indole test di erentiates 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
D. Bile salts and crystal violet
Colonies of Salmonella on SSA:
A. Colorless colonies with black center B. Colorless colonies w/o black center
C. Red colonies with black center
D. Red colonies w/o black center
A. Colorless colonies with black center
Which of the following is a correct pair?
A. S. aureus — Pink colonies on MSA
B. K. pneumoniae — Colorless on MAC
C. S. pneumoniae — Non-hemolytic on SBA
D. E.coli — Yellow colonies on XLD
D. E.coli — Yellow colonies on XLD
All members of Enterobacteriaceae are motile at 37C except:
- Klebsiella
- Proteus
- Shigella
- Yersinia
A. 1, 2, and 3
B.1, 3, and 4
C. 1 and 3
D. 1 and 4
B.1, 3, and 4
pH indicator of LIA:
A. Neutral Red
B. Phenol Red
C. Bromthymol blue
D. Bromcresol purple
D. Bromcresol purple
Yellow butt and Red slant in TSI tube indicate fermentation of:
A. Lactose
B. Glucose
C. LActose and Glucose
D. Lactose and/or Glucose
B. Glucose
Heat stable antigen of enterics located on their cell wall:
A. O
B. K
C. H
D. Vi
A. O
ONPG test allows organisms to be classified as lactose fermenters by testing which of the following:
A. B-lactamase
B. B-galactosidase
C. Lactose permease
D. Tryptophanase
B. B-galactosidase
Only oxidase-positive member of Enterobacteriaceae:
A. Shigella
B. Morganella
C. Plesiomonas
D. Edwardsiella
C. Plesiomonas
Vibrio cholerae colonies on TCBS:
A. Blue
B. Green
C. Yellow
D. Red
C. Yellow
Which of the following sets of results represent the most common reactions for Moraxella catarrhalis when tested in CTA sugar tubes?
A. Glucose: Negative; Maltose: Negative; Lactose: Negative; Sucrose: Negative
B. Glucose: Positive; Maltose: Negative; Lactose: Negative; Sucrose: Negative
C. Glucose: Positive; Maltose: Positive; Lactose: Negative; Sucrose: Negative
D. Glucose: Positive; Maltose: Negative; Lactose: Positive; Sucrose: Negative
ALL NEGATIVE !
A. Glucose: Negative; Maltose: Negative; Lactose: Negative; Sucrose: Negative
Neisseria lactamica can be di erentiated from Neisseria meningitidis through which of the following?
A. Colony morphology
B. Use of selective media
C. Glucose and maltose utilization
D. ONPG test
D. ONPG test
Isolates of suspected C. diphtheriae must be tested for in vitro production of exotoxin through:
A. Anton test
B. Elek test
C. Frei test
D. Mantoux test
B. Elek test
Lecithinase production, double zone hemolysis on sheep blood agar, and gram-stained morphology are all useful criteria in the identification of which of the following?
A. Clostridium perfringens
B. Streptococcus agalactiae
C. Escherichia coli
D. Clostridium tetani
A. Clostridium perfringens
Sensitivity test result of Group A streptococci (S. pyogenes) to Bacitracin and SXT respectively:
A. Susceptible and resistant
B. Resistant and susceptible
C. Both susceptible
D. Both resistant
A. 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 (LPS)
C. Takes up the crystal violet-iodine complex but is easily decolorize
D. Uses selective isolation media like colistin-nalidixic acid (CNA) agar
D. Uses selective isolation media like colistin-nalidixic acid (CNA) 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
C. Potassium permanganate
Stain for endospore:
A. Wayson
B. Leifson
C. Schaeffer-Fulton
D. Loeffler’s Alkaline Methylene Blue
C. Schaeffer-Fulton
Most common gas for sterilization:
A. Nitrogen dioxide
B. Chlorine dioxide
C. Ethylene oxide
D. Chlorhexidine gluconate
C. 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
A. 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. 121C/ 15 psi/ 15 mins
C. Dry heat sterilization
Uses a strip with varying concentration of antibiotic along its length and MIC can be obtained:
A. Kirby Bauer
B. Microplate dilution
C. Vitek System
D. E-Test
D. E-Test
0.5 Macfarland standard provides an optical density comparable to density of a bacterial suspension of:
A. 0.5 x 105 CFU/mL
B. 1.5 x 108 CFU/mL
C. 0.5 x 109 CFU/mL
D. 1.5 x 109 CFU/mL
B. 1.5 x 108 CFU/mL
In disk di usion testing, a delay of more than 15 minutes between placing the disks on an inoculated plate and incubation results to:
A. failure of antibiotic to di use in media
B. zones of smaller diameter will result
C. zones of larger diameter will result
D. no e ect of final zone diameter
C. 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 other mycobacteria
C. Actinomyces but not Nocardia
D. Corynebacterium diphtheriae but not other corynebacteria
A. 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. Plasmadization
D. Conjugation
D. 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
A. 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. Streptococcus pneumoniae
C. Streptococcus pyogenes
D. Streptococcus agalactiae
B. Streptococcus pneumoniae
Which of the tests provide the best di erentiation of L. monocytogenes & E. rhusopathiae?
A. Gram-stained smear, oxidase, optochin
B. Gram-stained smear, catalase, and motility
C. CAMP test, H2S production, Esculin hydrolysis
D. Reverse CAMP, gram-stained smear, b-hemolysis
C. CAMP test, H2S production, Esculin hydrolysis
Micrococcus and Staphylococcus species are di fferentiated 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
D. 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
A. 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
D. pH indicator in TCBS
LOA reaction of Klebsiella pneumoniae:
A. +–
B. ++-
C. -+-
D. +-+
A. +–
All are correct regarding Staphylococcus saprophyticus EXCEPT: A. Coagulase negative
B. Causes UTI in young women
C. Novobiocin sensitive
D. DNase negative
C. Novobiocin sensitive
Chocolate agar-based medium containing vancomycin, colistin, anisomycin & trimetoprim is known as
A. Thayer-Martin
B. Modified Thayer Martin
C. Martin-Lewis
D. New York City
C. Martin-Lewis
Which of the following is a wrong pair?
A. Brucella abortus - Bang’s bacillus
B. Neisseria meningitides - Meningococcus
C. Haemophilus influenzae - Koch Week’s bacillus
D. Mycobacterium avium intracellulare - Battey bacillus
C. Haemophilus influenzae - Koch Week’s bacillus
Positive result for DNase test:
A. Green
B. Pink
C. Clearing of medium
D. Hemolysis
C. 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
C. Type II-B1