ASCP Specialist in Chemistry
Certification Exam (SC) Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which analytical method is considered a reference method for serum
glucose measurement?
A. Hexokinase
B. Glucose oxidase
C. o-Toluidine
D. Somogyi-Nelson
Answer: A. Hexokinase
Rationale: The hexokinase method is highly specific and traceable to
reference standards, making it the reference method for glucose
determination.
, 2. Which electrolyte abnormality is most directly associated with
prolonged QT interval on ECG?
A. Hyperkalemia
B. Hypocalcemia
C. Hypernatremia
D. Hypermagnesemia
Answer: B. Hypocalcemia
Rationale: Low calcium levels delay ventricular repolarization, leading to
QT prolongation.
3. The primary buffer system regulating blood pH is the:
A. Phosphate buffer system
B. Protein buffer system
C. Bicarbonate–carbonic acid system
D. Hemoglobin buffer system
Answer: C. Bicarbonate–carbonic acid system
Rationale: This buffer system is the most important in extracellular fluid
and is regulated by lungs and kidneys.
4. Which enzyme is most specific for diagnosing acute myocardial
infarction?
A. AST
, B. LD
C. CK-MB
D. Cardiac troponin I
Answer: D. Cardiac troponin I
Rationale: Cardiac troponins are highly specific and sensitive markers of
myocardial injury.
5. An increased anion gap metabolic acidosis is commonly seen in:
A. Diarrhea
B. Renal tubular acidosis
C. Diabetic ketoacidosis
D. Vomiting
Answer: C. Diabetic ketoacidosis
Rationale: Accumulation of unmeasured acids such as ketones increases
the anion gap.
6. Which specimen is most appropriate for therapeutic drug monitoring
of tacrolimus?
A. Serum
B. Plasma
C. Whole blood
D. Urine
, Answer: C. Whole blood
Rationale: Tacrolimus partitions into red blood cells, requiring whole blood
measurement.
7. Which quality control rule is most sensitive to random error?
A. 2₍₂s₎
B. 1₍₂s₎
C. R₍₄s₎
D. 4₍₁s₎
Answer: C. R₍₄s₎
Rationale: The R₄s rule detects random error by identifying excessive range
between control results.
8. Increased serum alkaline phosphatase with normal GGT suggests:
A. Cholestatic liver disease
B. Alcoholic liver disease
C. Bone disease
D. Viral hepatitis
Answer: C. Bone disease
Rationale: Bone disorders elevate ALP without increasing GGT.
Certification Exam (SC) Practice
Questions And Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
1. Which analytical method is considered a reference method for serum
glucose measurement?
A. Hexokinase
B. Glucose oxidase
C. o-Toluidine
D. Somogyi-Nelson
Answer: A. Hexokinase
Rationale: The hexokinase method is highly specific and traceable to
reference standards, making it the reference method for glucose
determination.
, 2. Which electrolyte abnormality is most directly associated with
prolonged QT interval on ECG?
A. Hyperkalemia
B. Hypocalcemia
C. Hypernatremia
D. Hypermagnesemia
Answer: B. Hypocalcemia
Rationale: Low calcium levels delay ventricular repolarization, leading to
QT prolongation.
3. The primary buffer system regulating blood pH is the:
A. Phosphate buffer system
B. Protein buffer system
C. Bicarbonate–carbonic acid system
D. Hemoglobin buffer system
Answer: C. Bicarbonate–carbonic acid system
Rationale: This buffer system is the most important in extracellular fluid
and is regulated by lungs and kidneys.
4. Which enzyme is most specific for diagnosing acute myocardial
infarction?
A. AST
, B. LD
C. CK-MB
D. Cardiac troponin I
Answer: D. Cardiac troponin I
Rationale: Cardiac troponins are highly specific and sensitive markers of
myocardial injury.
5. An increased anion gap metabolic acidosis is commonly seen in:
A. Diarrhea
B. Renal tubular acidosis
C. Diabetic ketoacidosis
D. Vomiting
Answer: C. Diabetic ketoacidosis
Rationale: Accumulation of unmeasured acids such as ketones increases
the anion gap.
6. Which specimen is most appropriate for therapeutic drug monitoring
of tacrolimus?
A. Serum
B. Plasma
C. Whole blood
D. Urine
, Answer: C. Whole blood
Rationale: Tacrolimus partitions into red blood cells, requiring whole blood
measurement.
7. Which quality control rule is most sensitive to random error?
A. 2₍₂s₎
B. 1₍₂s₎
C. R₍₄s₎
D. 4₍₁s₎
Answer: C. R₍₄s₎
Rationale: The R₄s rule detects random error by identifying excessive range
between control results.
8. Increased serum alkaline phosphatase with normal GGT suggests:
A. Cholestatic liver disease
B. Alcoholic liver disease
C. Bone disease
D. Viral hepatitis
Answer: C. Bone disease
Rationale: Bone disorders elevate ALP without increasing GGT.
