MT(AAB) BASIC KNOWLEDGE PRACTICE ADDITIONAL
QUESTIONS (CLINICAL CHEMISTRY)
Question 41. The most common anticoagulant used for plasma chemistry tests is:
a) Sodium citrate
✅b) Lithium heparin
c) EDTA
d) Potassium oxalate
Rationale:
Lithium heparin prevents clotting by inhibiting thrombin and is the preferred anticoagulant for plasma
chemistry assays because it causes minimal interference with most analytes.
Question 42. The primary energy source for most cells is:
a) Protein
b) Fat
✅c) Glucose
d) Glycogen
Rationale:
Glucose is the main cellular fuel, metabolized via glycolysis and oxidative phosphorylation to produce
ATP, the body’s energy currency.
Question 43. The enzyme that catalyzes the conversion of glucose to glucose-6-phosphate is:
a) Aldolase
b) Glucose oxidase
✅c) Hexokinase
d) Pyruvate kinase
Rationale:
Hexokinase phosphorylates glucose in the first step of glycolysis, trapping it inside the cell for energy
production or storage.
Question 44. Which of the following enzymes is elevated in acute pancreatitis?
a) ALT
b) AST
✅c) Amylase
d) LDH
Rationale:
Amylase and lipase are pancreatic enzymes that increase in the bloodstream when the pancreas is
inflamed or injured.
Question 45. The reference method for glucose measurement uses which enzyme?
✅a) Hexokinase
b) Glucose oxidase
c) Peroxidase
d) Lactate dehydrogenase
, ESTUDYR
Rationale:
The hexokinase method is the most specific and reliable reference method for glucose because it’s less
subject to interference than glucose oxidase.
Question 46. A patient with prolonged fasting and low blood glucose likely has elevated:
a) Insulin
✅b) Glucagon
c) Cortisol
d) Thyroxine
Rationale:
Glucagon is secreted by pancreatic α-cells during fasting to raise blood glucose through glycogenolysis
and gluconeogenesis.
Question 47. Serum bilirubin is a breakdown product of:
a) Albumin
b) Fibrin
✅c) Hemoglobin
d) Collagen
Rationale:
Bilirubin forms when heme from hemoglobin is catabolized in the liver and spleen. It’s transported to
the liver for conjugation and excretion.
Question 48. Which fraction of bilirubin is water-soluble?
a) Unconjugated
✅b) Conjugated
c) Delta bilirubin
d) Indirect
Rationale:
Conjugated (direct) bilirubin is bound to glucuronic acid in the liver, making it water-soluble and
excretable in bile.
Question 49. Which enzyme is most specific for liver disease?
a) AST
✅b) ALT
c) ALP
d) LDH
Rationale:
Alanine aminotransferase (ALT) is found mainly in hepatocytes and rises predominantly in hepatocellular
injury, making it more specific for liver pathology than AST.
Question 50. Increased serum alkaline phosphatase (ALP) can be seen in:
✅a) Bone growth and liver disease
b) Renal failure
c) Myocardial infarction
d) Hemolytic anemia
Rationale:
ALP is elevated in disorders affecting bone or hepatobiliary systems (e.g., bone metastasis, biliary
obstruction).