2
MLT ASCP Chemistry Practice Questions with accurate
|| || || || || || ||
detailed answers ||
Which one of the following statements about acetaminophen metabolism is false?
|| || || || || || || || || ||
Choose the single best answer || || || ||
A. It is metabolized in the kidney
|| || || || || ||
B. It is largely metabolized in the liver to glucuronide and sulfonate conjugates
|| || || || || || || || || || || ||
C. A small amount is metabolized via cytochrome oxidase to a reactive benzoquinoneimine
|| || || || || || || || || || || || ||
intermediate
D. This intermediate becomes toxic to the liver once tissue glutathione becomes depleted -
|| || || || || || || || || || || || || ||
✔✔A; ||
The benzoquinoneimine intermediate produced in the liver as a result of hepatic
|| || || || || || || || || || || ||
cytochrome oxidase metabolism of acetaminophen is responsible for hepatic necrosis via
|| || || || || || || || || || ||
acylation of hepatic tissue. The treatment of acetaminophen toxicity includes the use of N-
|| || || || || || || || || || || || ||
acetylcysteine (Mucomyst), which acts as a glutathione substitute. The risk of hepatotoxicity
|| || || || || || || || || || ||
is predicted with the Rumack-Matthew nomogram, which uses the hours after ingestion
|| || || || || || || || || || || || ||
and plasma acetaminophen level to predict the probability of hepatotoxicity. Severe
|| || || || || || || || || || ||
hepatotoxicity can be fatal. || || ||
According to the 2010 ADA guidelines, HbA1C percent can be used as an assay to diagnose
|| || || || || || || || || || || || || || || ||
diabetes.
True/False - ✔✔T; || ||
The 2010 ADA Clinical Practice Recommendations added measurement of HbA1C as a
|| || || || || || || || || || || ||
diagnostic assay for diagnosis of diabetes. || || || || ||
,2
Which of the following conditions would make a sample unsuitable for lactic acid testing?
|| || || || || || || || || || || || ||
Choose the single best answer || || || ||
A. Movement of hand or arm during specimen collection
|| || || || || || || ||
B. Received in the lab on ice
|| || || || || ||
C. Centrifuged in a refrigerated centrifuge
|| || || || ||
D. Specimen centrifuged and plasma separated from cells less than 15 minutes after
|| || || || || || || || || || || || ||
collection - ✔✔A; || ||
Movement of the muscles in the hand or arm during specimen collection will falsely
|| || || || || || || || || || || || || ||
increase lactic acid concentration. A blood sample for lactic acid testing should be placed on
|| || || || || || || || || || || || || ||
ice immediately after collection, centrifuged within 15 minutes of collection, and plasma
|| || || || || || || || || || || || ||
immediately separated from cells following centrifugation. If possible, a refrigerated || || || || || || || || || ||
centrifuge should be used. || || ||
You are working in a clinical chemistry laboratory and are analyzing a plasma glucose
|| || || || || || || || || || || || || ||
sample. The sample is flagged by the analyzer for being "outside of linear range." You
|| || || || || || || || || || || || || || ||
manually dilute the sample 1:2 and rerun it. Again, you receive an "outside linear range"
|| || || || || || || || || || || || || || ||
alert. You decide to perform a different manual dilution. This time you manually dilute the
|| || || || || || || || || || || || || || ||
original sample again; this time using a 1:3 dilution. The instrument gives you a glucose
|| || || || || || || || || || || || || || ||
value of 150 mg/dL from this diluted sample. What is the actual patient glucose result that
|| || || || || || || || || || || || || || || ||
you should report to the physician?
|| || || || ||
Choose the single best answer || || || ||
A. 100 mg/dL
|| ||
B. 400 mg/dL
|| ||
C. 600 mg/dL
|| ||
D. 450 mg/dL
|| ||
E. 1200 mg/dL - ✔✔D;
|| || || ||
, 2
The correct response is option D: 450 mg/dl. A 1:3 dilution entails mixing one part patient
|| || || || || || || || || || || || || || || ||
sample with two parts diluent, for a total volume of 3 parts. In laboratory dilutions, the total
|| || || || || || || || || || || || || || || ||
volume is considered a dilution factor. The dilution factor in this question is 3. So a diluted
|| || || || || || || || || || || || || || || || || ||
sample with a value of 150 would need to be multiplied by 3 to obtain the correct final
|| || || || || || || || || || || || || || || || || ||
answer. 150 x 3 = 450 mg/dl. || || || || || ||
That portion of an enzyme which is separated from its cofactor is called a(n):
|| || || || || || || || || || || || ||
Choose the single best answer || || || ||
A. Partial enzyme
|| ||
B. Isoenzyme
||
C. Coenzyme
||
D. Apoenzyme - ✔✔D;
|| || ||
A partial enzyme is not an actual term used in the laboratory. An isoenzyme is a related
|| || || || || || || || || || || || || || || || ||
enzyme with a different chemical structure. Finally, a coenzyme is a non-protein molecule
|| || || || || || || || || || || || ||
(often a vitamin) that helps an enzyme become active.
|| || || || || || || ||
A low CSF glucose level is associated with all the following except:
|| || || || || || || || || || ||
Choose the single best answer || || || ||
A. Hyperglycemia
||
B. Fungal meningitis
|| ||
C. Toxoplasmosis
||
D. Hypoglycemia - ✔✔A;
|| || || ||
MLT ASCP Chemistry Practice Questions with accurate
|| || || || || || ||
detailed answers ||
Which one of the following statements about acetaminophen metabolism is false?
|| || || || || || || || || ||
Choose the single best answer || || || ||
A. It is metabolized in the kidney
|| || || || || ||
B. It is largely metabolized in the liver to glucuronide and sulfonate conjugates
|| || || || || || || || || || || ||
C. A small amount is metabolized via cytochrome oxidase to a reactive benzoquinoneimine
|| || || || || || || || || || || || ||
intermediate
D. This intermediate becomes toxic to the liver once tissue glutathione becomes depleted -
|| || || || || || || || || || || || || ||
✔✔A; ||
The benzoquinoneimine intermediate produced in the liver as a result of hepatic
|| || || || || || || || || || || ||
cytochrome oxidase metabolism of acetaminophen is responsible for hepatic necrosis via
|| || || || || || || || || || ||
acylation of hepatic tissue. The treatment of acetaminophen toxicity includes the use of N-
|| || || || || || || || || || || || ||
acetylcysteine (Mucomyst), which acts as a glutathione substitute. The risk of hepatotoxicity
|| || || || || || || || || || ||
is predicted with the Rumack-Matthew nomogram, which uses the hours after ingestion
|| || || || || || || || || || || || ||
and plasma acetaminophen level to predict the probability of hepatotoxicity. Severe
|| || || || || || || || || || ||
hepatotoxicity can be fatal. || || ||
According to the 2010 ADA guidelines, HbA1C percent can be used as an assay to diagnose
|| || || || || || || || || || || || || || || ||
diabetes.
True/False - ✔✔T; || ||
The 2010 ADA Clinical Practice Recommendations added measurement of HbA1C as a
|| || || || || || || || || || || ||
diagnostic assay for diagnosis of diabetes. || || || || ||
,2
Which of the following conditions would make a sample unsuitable for lactic acid testing?
|| || || || || || || || || || || || ||
Choose the single best answer || || || ||
A. Movement of hand or arm during specimen collection
|| || || || || || || ||
B. Received in the lab on ice
|| || || || || ||
C. Centrifuged in a refrigerated centrifuge
|| || || || ||
D. Specimen centrifuged and plasma separated from cells less than 15 minutes after
|| || || || || || || || || || || || ||
collection - ✔✔A; || ||
Movement of the muscles in the hand or arm during specimen collection will falsely
|| || || || || || || || || || || || || ||
increase lactic acid concentration. A blood sample for lactic acid testing should be placed on
|| || || || || || || || || || || || || ||
ice immediately after collection, centrifuged within 15 minutes of collection, and plasma
|| || || || || || || || || || || || ||
immediately separated from cells following centrifugation. If possible, a refrigerated || || || || || || || || || ||
centrifuge should be used. || || ||
You are working in a clinical chemistry laboratory and are analyzing a plasma glucose
|| || || || || || || || || || || || || ||
sample. The sample is flagged by the analyzer for being "outside of linear range." You
|| || || || || || || || || || || || || || ||
manually dilute the sample 1:2 and rerun it. Again, you receive an "outside linear range"
|| || || || || || || || || || || || || || ||
alert. You decide to perform a different manual dilution. This time you manually dilute the
|| || || || || || || || || || || || || || ||
original sample again; this time using a 1:3 dilution. The instrument gives you a glucose
|| || || || || || || || || || || || || || ||
value of 150 mg/dL from this diluted sample. What is the actual patient glucose result that
|| || || || || || || || || || || || || || || ||
you should report to the physician?
|| || || || ||
Choose the single best answer || || || ||
A. 100 mg/dL
|| ||
B. 400 mg/dL
|| ||
C. 600 mg/dL
|| ||
D. 450 mg/dL
|| ||
E. 1200 mg/dL - ✔✔D;
|| || || ||
, 2
The correct response is option D: 450 mg/dl. A 1:3 dilution entails mixing one part patient
|| || || || || || || || || || || || || || || ||
sample with two parts diluent, for a total volume of 3 parts. In laboratory dilutions, the total
|| || || || || || || || || || || || || || || ||
volume is considered a dilution factor. The dilution factor in this question is 3. So a diluted
|| || || || || || || || || || || || || || || || || ||
sample with a value of 150 would need to be multiplied by 3 to obtain the correct final
|| || || || || || || || || || || || || || || || || ||
answer. 150 x 3 = 450 mg/dl. || || || || || ||
That portion of an enzyme which is separated from its cofactor is called a(n):
|| || || || || || || || || || || || ||
Choose the single best answer || || || ||
A. Partial enzyme
|| ||
B. Isoenzyme
||
C. Coenzyme
||
D. Apoenzyme - ✔✔D;
|| || ||
A partial enzyme is not an actual term used in the laboratory. An isoenzyme is a related
|| || || || || || || || || || || || || || || || ||
enzyme with a different chemical structure. Finally, a coenzyme is a non-protein molecule
|| || || || || || || || || || || || ||
(often a vitamin) that helps an enzyme become active.
|| || || || || || || ||
A low CSF glucose level is associated with all the following except:
|| || || || || || || || || || ||
Choose the single best answer || || || ||
A. Hyperglycemia
||
B. Fungal meningitis
|| ||
C. Toxoplasmosis
||
D. Hypoglycemia - ✔✔A;
|| || || ||
