MMSC438 EXAM 1 2025 QUESTIONS AND
ANSWERS
The gene mecA is responsible for MRSA. The most accurate method for the detection of MRSA
is:
a. Latex agglutination for PBP2a
b. Cefoxitin disc or MIC testing
c. Oxacillin agar screening
d. PCR - ANS D. PCR
An antimicrobial susceptibility concentration separating a susceptible drug concentration from
an intermediate is called a (an):
A. Antibiogram.
B. Assurance.
C. Breakpoint.
D. Spectrum. - ANS C. Breakpoint
When testing activity of antimicrobial drug combinations, if two drugs together produce
substantially greater susceptibility than the sum of the individual effects, it is known as...
A. Antagonism
B. Additive
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,C. Synergy
D. Indifference - ANS C. Synergy
In order to determine if an isolate of Streptococcus pneumoniae is penicillin-resistant,
screening can be performing using a(n)______ disc test.
A. cefoxitin
B. penicillin
C. optochin
D. oxacillin - ANS D. oxacillin
__________ is considered a specimen collection/clerical error and will generally result in
specimen rejection.
A. Missing medical record (ID) number on requisition
B. Inappropriate specimen for culture requested
C. Specimen quantity insufficient
D. Duplicate specimen same day
E. All of the above - ANS E. All of the above
The minimal bactericidal concentration is the concentration of an antimicrobial agent...
A. Needed to prevent visually discernible growth.
B. Reducing viable organism growth by 99.9%.
C. Always equal to the MIC.
D. Toxic to the patient. - ANS B. Reducing viable organism growth by 99.9%.
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, Standard disk diffusion tests on Gram-negative rods, such as E. coli, utilize which of the
following media and culture conditions?
A. Mueller Hinton agar, 35oC, 5% CO2, 16-18 hours
B. Mueller Hinton agar, 35oC, ambient air, 16-18 hours
C. Mueller Hinton agar, 20oC, 5% CO2, 20 hours
D. Mueller Hinton with 5% SBA, 35oC, 5% CO2, 16-18 hours - ANS B. Mueller Hinton agar,
35oC, ambient air, 16-18 hours
An antibiogram:
A. Involves the collection of statistical data for every organism tested at an institution.
B. Is a profile of bacterial susceptibility and resistance patterns against a set group of
antimicrobials.
C. Monitors resistance patterns at the institution.
D. All of the above - ANS D. All of the above
Standard Safety Precautions assume...
A. Sweat and tears are infectious.
B. Blood and vaginal secretions are infectious.
C. Feces and urine are infectious.
D. Vomit and nasal secretions are infectious. - ANS B. Blood and vaginal secretions are
infectious.
Vancomycin is primarily used to treat infections caused by:
A. Mycobacteria.
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ANSWERS
The gene mecA is responsible for MRSA. The most accurate method for the detection of MRSA
is:
a. Latex agglutination for PBP2a
b. Cefoxitin disc or MIC testing
c. Oxacillin agar screening
d. PCR - ANS D. PCR
An antimicrobial susceptibility concentration separating a susceptible drug concentration from
an intermediate is called a (an):
A. Antibiogram.
B. Assurance.
C. Breakpoint.
D. Spectrum. - ANS C. Breakpoint
When testing activity of antimicrobial drug combinations, if two drugs together produce
substantially greater susceptibility than the sum of the individual effects, it is known as...
A. Antagonism
B. Additive
1 @COPYRIGHT THEBRIGHT 2025/2026
,C. Synergy
D. Indifference - ANS C. Synergy
In order to determine if an isolate of Streptococcus pneumoniae is penicillin-resistant,
screening can be performing using a(n)______ disc test.
A. cefoxitin
B. penicillin
C. optochin
D. oxacillin - ANS D. oxacillin
__________ is considered a specimen collection/clerical error and will generally result in
specimen rejection.
A. Missing medical record (ID) number on requisition
B. Inappropriate specimen for culture requested
C. Specimen quantity insufficient
D. Duplicate specimen same day
E. All of the above - ANS E. All of the above
The minimal bactericidal concentration is the concentration of an antimicrobial agent...
A. Needed to prevent visually discernible growth.
B. Reducing viable organism growth by 99.9%.
C. Always equal to the MIC.
D. Toxic to the patient. - ANS B. Reducing viable organism growth by 99.9%.
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, Standard disk diffusion tests on Gram-negative rods, such as E. coli, utilize which of the
following media and culture conditions?
A. Mueller Hinton agar, 35oC, 5% CO2, 16-18 hours
B. Mueller Hinton agar, 35oC, ambient air, 16-18 hours
C. Mueller Hinton agar, 20oC, 5% CO2, 20 hours
D. Mueller Hinton with 5% SBA, 35oC, 5% CO2, 16-18 hours - ANS B. Mueller Hinton agar,
35oC, ambient air, 16-18 hours
An antibiogram:
A. Involves the collection of statistical data for every organism tested at an institution.
B. Is a profile of bacterial susceptibility and resistance patterns against a set group of
antimicrobials.
C. Monitors resistance patterns at the institution.
D. All of the above - ANS D. All of the above
Standard Safety Precautions assume...
A. Sweat and tears are infectious.
B. Blood and vaginal secretions are infectious.
C. Feces and urine are infectious.
D. Vomit and nasal secretions are infectious. - ANS B. Blood and vaginal secretions are
infectious.
Vancomycin is primarily used to treat infections caused by:
A. Mycobacteria.
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