Laboratory Science Clinical Chemistry

Question 1

What is the reference range for fasting blood glucose in a non-diabetic adult?

Accepted Answer

70–99 mg/dL

Answer

Normal fasting plasma glucose is 70–99 mg/dL; values of 100–125 mg/dL indicate prediabetes, and ≥126 mg/dL on two occasions diagnoses diabetes mellitus.

Question 2

Which enzyme is the primary cardiac biomarker used to diagnose acute myocardial infarction?

Accepted Answer

Troponin I or T

Answer

Cardiac troponin I and T are highly specific to myocardial cells; elevated levels in blood indicate cardiomyocyte necrosis and are the gold standard for diagnosing AMI.

Question 3

What does the HbA1c test measure?

Accepted Answer

Average blood glucose over the past 2–3 months

Answer

HbA1c measures the percentage of hemoglobin glycated by glucose, reflecting average blood glucose over 2–3 months (the lifespan of RBCs), used to monitor diabetes management.

Question 4

Elevated serum creatinine is most indicative of dysfunction in which organ?

Accepted Answer

Kidney

Answer

Creatinine is a muscle metabolism byproduct filtered by the kidneys; elevated serum creatinine indicates reduced glomerular filtration rate (GFR) and kidney dysfunction.

Question 5

Which liver enzyme is most specific for hepatocellular damage?

Accepted Answer

ALT (alanine aminotransferase)

Answer

ALT is predominantly found in liver cells, making it more specific for hepatocellular injury than AST, which is also found in heart and skeletal muscle.

Laboratory Science Practice Test

Laboratory Science Practice Test

Laboratory Science Clinical Chemistry