AMT MLS Exam Questions AND Correct Answers
A 20-year-old male presents to the Emergency room with
heavy urethral discharge that had been present for three
days. He has been sexually active with several partners and
has used no contraceptives. A culture of the discharge grows a
gram-negative diplococci with adjacent sides that are
flattened and is oxidase positive. What is the likely organism?
a.Chlamydia trachomatis
b.Neisseria gonorrhoeae
c.Treponema pallidum
d.Trichomonas vaginalis - ✔✔Correct Answer: Neisseria
gonorrhoeae
Neisseria gonorrhoeae is a sexually transmitted, oxidase
positive, gram negative diplococci that can cause urethral
discharge in males and females.
A 70-year-old female with a previous knee injury has joint
replacement surgery. The surgery goes well, and she is
discharged from the hospital to a rehabilitation facility to
receive post-operative care and physical therapy. One week
later the incision becomes inflamed and begins oozing a
,discharge. A gram stain of the discharge shows many white
blood cells and gram-positive cocci in clusters. The isolate
recovered is a cream-yellow beta-hemolytic colony that is
catalase and coagulase positive. What is the likely organism?
a.Enterococcus faecalis
b.Staphylococcus aureus
c.Staphylococcus epidermidis
d.Streptococcus pyogenes - ✔✔Correct Answer:
Staphylococcus aureus
Staphylococcus aureus is a gram-positive cocci in clusters that
generally yields a cream-yellow beta-hemolytic colony that is
catalase and coagulase positive. Streptococcus pyogenes and
Enterococcus faecalis are gram positive cocci that are catalase
negative. Staphylococcus epidermidis is coagulase negative.
A gram-negative rod > 100,000 col/cc is recovered from a
midstream urine. The isolate is swarming over the blood
plate, produces hydrogen sulfide on TSIA, and hydrolyzes
urea, indole negative and ornithine positive. What is the likely
organism identification?
,a.Morganella morganii
b.Proteus mirabilis
c.Proteus penneri
d.Proteus vulgaris - ✔✔Correct Answer: Proteus mirabilis
Proteus mirabilis is a commensal species in the
gastrointestinal tract of humans. It is widely disseminated in
the environment and recognized as an opportunistic
pathogen.
Proteus vulgaris is indole positive and ornithine negative.
Proteus penneri is ornithine negative. Morganella morganii is
indole positive and H2S negative on TSIA.
A procedure uses the following steps:
1. Antibody labeled with a fluorochrome directed against the
desired antigen is added to a slide with the specimen that
potentially contains the desired antigen being tested for.
2. Following incubation, the slide is washed.
3. The slide is then observed under a fluorescent microscope.
Which of the following does the above procedure describe?
, a.Direct fluorescent immunoassay
b.Flow cytometry (FC) panel
c.Indirect fluorescent immunoassay
d.Recombinant ImmunoBlot Assay - ✔✔Correct Answer:
Direct fluorescent immunoassay
In a direct assay of any kind, the antibody is conjugated
directly to the label and then this antibody-label conjugate is
added directly to the sample that contains the antigen being
tested for. In the case of a fluorescent assay the label is a
fluorochrome that will fluoresce under certain wavelengths of
light showing the presence of the antigen being tested for.
Absorbance can be calculated easily from percent
transmission using which calculation?
a.2 - log10 %T
b.2 + log10 %T
c.log10 %T - 2
d.log10 %T + 2 - ✔✔a. 2 - log10 %T
A 20-year-old male presents to the Emergency room with
heavy urethral discharge that had been present for three
days. He has been sexually active with several partners and
has used no contraceptives. A culture of the discharge grows a
gram-negative diplococci with adjacent sides that are
flattened and is oxidase positive. What is the likely organism?
a.Chlamydia trachomatis
b.Neisseria gonorrhoeae
c.Treponema pallidum
d.Trichomonas vaginalis - ✔✔Correct Answer: Neisseria
gonorrhoeae
Neisseria gonorrhoeae is a sexually transmitted, oxidase
positive, gram negative diplococci that can cause urethral
discharge in males and females.
A 70-year-old female with a previous knee injury has joint
replacement surgery. The surgery goes well, and she is
discharged from the hospital to a rehabilitation facility to
receive post-operative care and physical therapy. One week
later the incision becomes inflamed and begins oozing a
,discharge. A gram stain of the discharge shows many white
blood cells and gram-positive cocci in clusters. The isolate
recovered is a cream-yellow beta-hemolytic colony that is
catalase and coagulase positive. What is the likely organism?
a.Enterococcus faecalis
b.Staphylococcus aureus
c.Staphylococcus epidermidis
d.Streptococcus pyogenes - ✔✔Correct Answer:
Staphylococcus aureus
Staphylococcus aureus is a gram-positive cocci in clusters that
generally yields a cream-yellow beta-hemolytic colony that is
catalase and coagulase positive. Streptococcus pyogenes and
Enterococcus faecalis are gram positive cocci that are catalase
negative. Staphylococcus epidermidis is coagulase negative.
A gram-negative rod > 100,000 col/cc is recovered from a
midstream urine. The isolate is swarming over the blood
plate, produces hydrogen sulfide on TSIA, and hydrolyzes
urea, indole negative and ornithine positive. What is the likely
organism identification?
,a.Morganella morganii
b.Proteus mirabilis
c.Proteus penneri
d.Proteus vulgaris - ✔✔Correct Answer: Proteus mirabilis
Proteus mirabilis is a commensal species in the
gastrointestinal tract of humans. It is widely disseminated in
the environment and recognized as an opportunistic
pathogen.
Proteus vulgaris is indole positive and ornithine negative.
Proteus penneri is ornithine negative. Morganella morganii is
indole positive and H2S negative on TSIA.
A procedure uses the following steps:
1. Antibody labeled with a fluorochrome directed against the
desired antigen is added to a slide with the specimen that
potentially contains the desired antigen being tested for.
2. Following incubation, the slide is washed.
3. The slide is then observed under a fluorescent microscope.
Which of the following does the above procedure describe?
, a.Direct fluorescent immunoassay
b.Flow cytometry (FC) panel
c.Indirect fluorescent immunoassay
d.Recombinant ImmunoBlot Assay - ✔✔Correct Answer:
Direct fluorescent immunoassay
In a direct assay of any kind, the antibody is conjugated
directly to the label and then this antibody-label conjugate is
added directly to the sample that contains the antigen being
tested for. In the case of a fluorescent assay the label is a
fluorochrome that will fluoresce under certain wavelengths of
light showing the presence of the antigen being tested for.
Absorbance can be calculated easily from percent
transmission using which calculation?
a.2 - log10 %T
b.2 + log10 %T
c.log10 %T - 2
d.log10 %T + 2 - ✔✔a. 2 - log10 %T