UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
1. Proper media for culture of a urethral discharge from d
a man include:
a. Sheep blood and phenylethyl alcohol agars
b. Eosin-methylene blue and sheep blood agars
c. Thioglycollate broth and chocolate agars d. Choco-
late and modified Thayer-Martin agars
2. Which selective medium is used for the isolation c
of gram negative microorganisms? a. Columbia CNA
with 5% sheep blood
b. Trypticase soy agar with 5% sheep blood c. Eosin
methylene blue
d. Phenyl ethyl alcohol
3. A sheep blood plate inoculated with 0.001mL of urine d
grows 80 colonies of Tracyellastaton spp. How many
colony forming units per mL of urine should be report-
ed?
a. 80
b. 800
c. 8,000
d. 80,000
4. The lowest concentration of antibiotic that inhibits a
growth of a test organism is the:
a. minimum inhibitory concentration
b. serum inhibitory concentration
c. minimum bactericidal titer
d. maximum inhibitory titer
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
5. In the Kirby-Bauer disc diffusion susceptibility test, c
which variable is critical when testing Pseudomonas
species for antibiotic susceptibility to aminoglyco-
sides?
a. incubation temperature
b. duration of incubation
c. cation content of media
d. depth of agar
6. In disk diffusion susceptibility testing, as an antimicro- b
bial agent diffuses away from the disk, the concentra-
tion of antibiotic is:
a. increased
b. decreased
c. unchanged
d. inoculum dependent
7. Susceptibility testing was performed on quality con- b
trol organisms using a new media lot number yield-
ed zone sizes that were too small for all antibiotics
tested. The testing was repeated using media from a
previously used lot number, and all zone sizes were
acceptable. Which of the following best explains the
unacceptable zone sizes?
a. antibiotic disks were not stored with the proper
desiccant
b. depth of the media was too thick
c. depth of the media was too thin
d. antibiotic disk were not properly applied to the
media
8. b
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
Which of the following factors would make an organ-
ism appear to be more resistant on a disk diffusion
susceptibility test?
a. too little agar in the plate
b. too many organisms in the inoculum
c. presence of 0.5% NaCl in the medium
d. medium with a pH of 7.4
9. Chocolate agar base containing vancomycin, colistin, d
and nystatin is also known as:
a. EMB agar
b. Modified Thayer-Martin agar
c. Columbia CNA agar
d. Martin Lewis agar
10. A gram stain from a swab of a leg wound reveals: d
Many neutrophils No squamous epithelial Moderate
gram positive cocci in chains Moderate gram negative
bacilli
Select the appropriate media that will SELECTIVELY
isolate each organism.
a. KV-laked agar, Thayer-Martin
b. Sheep blood, MacConkey
c. Columbia CNA, chocolate
d. Columbia CNA, MacConkey
11. SPS is used as an anticoagulant for blood cultures c
because it:
a. inactivates penicillin and cephalosporin b. prevents
clumping of red cells
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
c. inactivates neutrophils and components of serum
complement
d. facilitates growth of anaerobes
12. Second-generation cephalosporins can be represent- d
ed by:
a. cefotetan
b. ceftriaxone
c. cephalothin
d. cefoxitin
13. An antibiotic that inhibits cell wall synthesis is: b
a. chloramphenicol
b. penicillin
c. sulfamethoxazole
d. colistin
14. The optimal wound specimen for culture of anaerobic c
organisms should be:
a. A swab of lesion obtained before administration of
antibiotics
b. A swab of lesion obtained after administration of
antibiotics
c. A syringe filled with pus, obtained before adminis-
tration of antibiotics
d. A syringe filled with pus, obtained after administra-
tion of antibiotics
15. A vaginal/rectal swab is collected from a pregnant b
patient to screen for group B Streptococcus coloniza-
tion. What is the best medium to use for specimen
inoculation?
a. blood agar
Questions and Answers Guide 2026
1. Proper media for culture of a urethral discharge from d
a man include:
a. Sheep blood and phenylethyl alcohol agars
b. Eosin-methylene blue and sheep blood agars
c. Thioglycollate broth and chocolate agars d. Choco-
late and modified Thayer-Martin agars
2. Which selective medium is used for the isolation c
of gram negative microorganisms? a. Columbia CNA
with 5% sheep blood
b. Trypticase soy agar with 5% sheep blood c. Eosin
methylene blue
d. Phenyl ethyl alcohol
3. A sheep blood plate inoculated with 0.001mL of urine d
grows 80 colonies of Tracyellastaton spp. How many
colony forming units per mL of urine should be report-
ed?
a. 80
b. 800
c. 8,000
d. 80,000
4. The lowest concentration of antibiotic that inhibits a
growth of a test organism is the:
a. minimum inhibitory concentration
b. serum inhibitory concentration
c. minimum bactericidal titer
d. maximum inhibitory titer
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
5. In the Kirby-Bauer disc diffusion susceptibility test, c
which variable is critical when testing Pseudomonas
species for antibiotic susceptibility to aminoglyco-
sides?
a. incubation temperature
b. duration of incubation
c. cation content of media
d. depth of agar
6. In disk diffusion susceptibility testing, as an antimicro- b
bial agent diffuses away from the disk, the concentra-
tion of antibiotic is:
a. increased
b. decreased
c. unchanged
d. inoculum dependent
7. Susceptibility testing was performed on quality con- b
trol organisms using a new media lot number yield-
ed zone sizes that were too small for all antibiotics
tested. The testing was repeated using media from a
previously used lot number, and all zone sizes were
acceptable. Which of the following best explains the
unacceptable zone sizes?
a. antibiotic disks were not stored with the proper
desiccant
b. depth of the media was too thick
c. depth of the media was too thin
d. antibiotic disk were not properly applied to the
media
8. b
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
Which of the following factors would make an organ-
ism appear to be more resistant on a disk diffusion
susceptibility test?
a. too little agar in the plate
b. too many organisms in the inoculum
c. presence of 0.5% NaCl in the medium
d. medium with a pH of 7.4
9. Chocolate agar base containing vancomycin, colistin, d
and nystatin is also known as:
a. EMB agar
b. Modified Thayer-Martin agar
c. Columbia CNA agar
d. Martin Lewis agar
10. A gram stain from a swab of a leg wound reveals: d
Many neutrophils No squamous epithelial Moderate
gram positive cocci in chains Moderate gram negative
bacilli
Select the appropriate media that will SELECTIVELY
isolate each organism.
a. KV-laked agar, Thayer-Martin
b. Sheep blood, MacConkey
c. Columbia CNA, chocolate
d. Columbia CNA, MacConkey
11. SPS is used as an anticoagulant for blood cultures c
because it:
a. inactivates penicillin and cephalosporin b. prevents
clumping of red cells
, UAMS Microbiology Final Exam Practice
Questions and Answers Guide 2026
c. inactivates neutrophils and components of serum
complement
d. facilitates growth of anaerobes
12. Second-generation cephalosporins can be represent- d
ed by:
a. cefotetan
b. ceftriaxone
c. cephalothin
d. cefoxitin
13. An antibiotic that inhibits cell wall synthesis is: b
a. chloramphenicol
b. penicillin
c. sulfamethoxazole
d. colistin
14. The optimal wound specimen for culture of anaerobic c
organisms should be:
a. A swab of lesion obtained before administration of
antibiotics
b. A swab of lesion obtained after administration of
antibiotics
c. A syringe filled with pus, obtained before adminis-
tration of antibiotics
d. A syringe filled with pus, obtained after administra-
tion of antibiotics
15. A vaginal/rectal swab is collected from a pregnant b
patient to screen for group B Streptococcus coloniza-
tion. What is the best medium to use for specimen
inoculation?
a. blood agar
