Question 1
The most sensitive substrate for the detection of beta-lactamases is:
A. penicillin
B. ampicillin
C. cefoxitin
D. nitrocefin
CORRECT ANSWER
D. nitrocefin
The chromogenic cephalosporin test using nitrocefin is the most sensitive and specific
test for detection of beta lactamase. Acidimetric tests employing penicillin are less
expensive, but not as sensitive, as the nitrocefin assay.
Question 2
A glucose determination was read on a spectrophotometer. The absorbance reading of the
standard was 0.30. The absorbance reading of the unknown was 0.20. The value of the
unknown is:
A. 2/3 of the standard
B. 3/5 of the standard
C. the same as the standard
D. 1½ x the standard
CORRECT ANSWER
A. 2/3 of the standard
1
@THE STUDY VAULT
, The value of the unknown is a ratio of the absorbance reading of the unknown to the
absorbance reading of the standard.
Question 3
Pre-analytical errors are major contributors to total laboratory errors. Examples of obvious
pre-analytical errors are:
A. specimen collected in the wrong container
B. unlabeled specimen
C. QNS, hemolyzed or lipemic specimens
D. all of the above
CORRECT ANSWER
D. all of the above
All are examples of pre-analytical error.
Question 4
Hemoglobin S can be separated from hemoglobin D by which of the following methods?
A. citrate agar gel electrophoresis at pH 5.9
B. thin-layer chromatography
C. alkali denaturation
D. agarose gel electrophoresis at pH 8.4
CORRECT ANSWER
A. citrate agar gel electrophoresis at pH 5.9
2
@THE STUDY VAULT
, HgbD migrates with S in alkaline electrophoresis but migrates with A in citrate acid
electrophoresis. Alkaline denaturation is used in detecting and differentiating HgbF from
other forms.
Question 5
Which description best fits the Donath-Landsteiner antibody?
A. IgM cold agglutinin
B. biphasic IgM hemolysin
C. IgG biphasic hemolysin
D. IgG warm agglutinin
CORRECT ANSWER
C. IgG biphasic hemolysin
The Donath-Landsteiner antibody is a biphasic, complement-fixing IgG antibody.
Question 6
The sodium content (in grams) in 100 g of NaCl (atomic weights: Na = 23.0, Cl = 35.5) is
approximately:
A. 10
B. 20
C. 40
D. 60
CORRECT ANSWER
C. 40
This is a ratio calculation. 100 (g of NaCl) to 58.5 (gram equivalent weight of NaCl) =
1.709. 23 (gram equivalent weight of Na) × 1.709 = grams of Na in 100g NaCl.
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@THE STUDY VAULT
, Question 7
In the Clauss fibrinogen method, the time to clot formation in plasma is measured after
the addition of:
A. calcium
B. thrombin
C. phospholipids
D. kaolin
CORRECT ANSWER
B. thrombin
In a Clauss fibrinogen, a standard amount of thrombin is added to diluted plasma, and
the time required for clot formation is recorded.
Question 8
What is the most likely mode of transmission for bloodborne pathogens in laboratory
acquired infections?
A. parenteral inoculation of blood
B. contact with intact skin
C. airborne transmission
D. fecal-oral transmission
CORRECT ANSWER
A. parenteral inoculation of blood
The correct answer is a, parenteral inoculation of blood. The other distractors are not likely
transmission modes for bloodborne pathogens.
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@THE STUDY VAULT
The most sensitive substrate for the detection of beta-lactamases is:
A. penicillin
B. ampicillin
C. cefoxitin
D. nitrocefin
CORRECT ANSWER
D. nitrocefin
The chromogenic cephalosporin test using nitrocefin is the most sensitive and specific
test for detection of beta lactamase. Acidimetric tests employing penicillin are less
expensive, but not as sensitive, as the nitrocefin assay.
Question 2
A glucose determination was read on a spectrophotometer. The absorbance reading of the
standard was 0.30. The absorbance reading of the unknown was 0.20. The value of the
unknown is:
A. 2/3 of the standard
B. 3/5 of the standard
C. the same as the standard
D. 1½ x the standard
CORRECT ANSWER
A. 2/3 of the standard
1
@THE STUDY VAULT
, The value of the unknown is a ratio of the absorbance reading of the unknown to the
absorbance reading of the standard.
Question 3
Pre-analytical errors are major contributors to total laboratory errors. Examples of obvious
pre-analytical errors are:
A. specimen collected in the wrong container
B. unlabeled specimen
C. QNS, hemolyzed or lipemic specimens
D. all of the above
CORRECT ANSWER
D. all of the above
All are examples of pre-analytical error.
Question 4
Hemoglobin S can be separated from hemoglobin D by which of the following methods?
A. citrate agar gel electrophoresis at pH 5.9
B. thin-layer chromatography
C. alkali denaturation
D. agarose gel electrophoresis at pH 8.4
CORRECT ANSWER
A. citrate agar gel electrophoresis at pH 5.9
2
@THE STUDY VAULT
, HgbD migrates with S in alkaline electrophoresis but migrates with A in citrate acid
electrophoresis. Alkaline denaturation is used in detecting and differentiating HgbF from
other forms.
Question 5
Which description best fits the Donath-Landsteiner antibody?
A. IgM cold agglutinin
B. biphasic IgM hemolysin
C. IgG biphasic hemolysin
D. IgG warm agglutinin
CORRECT ANSWER
C. IgG biphasic hemolysin
The Donath-Landsteiner antibody is a biphasic, complement-fixing IgG antibody.
Question 6
The sodium content (in grams) in 100 g of NaCl (atomic weights: Na = 23.0, Cl = 35.5) is
approximately:
A. 10
B. 20
C. 40
D. 60
CORRECT ANSWER
C. 40
This is a ratio calculation. 100 (g of NaCl) to 58.5 (gram equivalent weight of NaCl) =
1.709. 23 (gram equivalent weight of Na) × 1.709 = grams of Na in 100g NaCl.
3
@THE STUDY VAULT
, Question 7
In the Clauss fibrinogen method, the time to clot formation in plasma is measured after
the addition of:
A. calcium
B. thrombin
C. phospholipids
D. kaolin
CORRECT ANSWER
B. thrombin
In a Clauss fibrinogen, a standard amount of thrombin is added to diluted plasma, and
the time required for clot formation is recorded.
Question 8
What is the most likely mode of transmission for bloodborne pathogens in laboratory
acquired infections?
A. parenteral inoculation of blood
B. contact with intact skin
C. airborne transmission
D. fecal-oral transmission
CORRECT ANSWER
A. parenteral inoculation of blood
The correct answer is a, parenteral inoculation of blood. The other distractors are not likely
transmission modes for bloodborne pathogens.
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@THE STUDY VAULT
