MMSC 407 CLINICAL CHEMISTRY
PRACTICE FINAL EXAMINATION ACTUAL
QUESTIONS ASSESSMENT 2026 DETAILED
FIFTY QUESTIONS WITH VERY
ELABORATED CORRECTLY DEFINED
SOLUTIONS WELL ARRANGED GRADED A+
⩥ Why does hemolysis affect electrolyte measurement in blood
samples?
A. It dilutes plasma volume
B. It causes protein binding of electrolytes
C. It releases intracellular ions into the plasma or serum
D. It neutralizes all ions present. Answer: C. It releases intracellular ions
into the plasma or serum
⩥ Which of the following laboratory artifacts can result in falsely
elevated potassium readings?
A. Lipemia
B. Icterus
C. Hemolysis
D. Dehydration. Answer: C. Hemolysis
,⩥ Which electrolyte is most directly involved in maintaining the resting
membrane potential of cells?
A. Calcium
B. Potassium
C. Magnesium
D. Chloride. Answer: B. Potassium
⩥ The normal reference range for serum chloride is approximately:
A. 98-107 mmol/L
B. 75-90 mmol/L
C. 110-125 mmol/L
D. 60-70 mmol/L. Answer: A. 98-107 mmol/L
⩥ Which statement correctly matches the electrolyte with normal
reference range?
A. Calcium: 1.0-2.0 mmol/L
B. Potassium: 2.0-3.0 mmol/L
C. Sodium: 135-145 mmol/L
D. Magnesium: 0.2-0.5 mmol/L. Answer: C. Sodium: 135-145 mmol/L
⩥ Which form of an electrolyte is most important for immediate
physiological functions such as muscle contraction and nerve signaling?
A. Total
,B. Bound
C. Ionized
D. Excreted. Answer: C. Ionized
⩥ Why might total electrolyte levels not always reflect the
physiologically active portion of an electrolyte?
A. Total levels include electrolytes excreted in urine
B. Total levels exclude bound forms
C. Total levels include both bound and free forms, but only ionized
forms are active
D. Total levels only measure intracellular content. Answer: C. Total
levels include both bound and free forms, but only ionized forms are
active
⩥ Which of the following is a common cause of hyponatremia?
A. Dehydration due to water loss
B. Excessive water intake or syndrome of inappropriate antidiuretic
hormone secretion(SIADH)
C. Diabetes mellitus
D. Hyperaldosteronism. Answer: B. Excessive water intake or syndrome
of inappropriate antidiuretic hormone secretion(SIADH)
⩥ Which of the following is a common cause of hypokalemia?
A. Renal failure
, B. Diuretic use(e.g, loop or thiazide diuretics)
C. Addison's disease
D. Tissue breakdown. Answer: B. Diuretic use(e.g, loop or thiazide
diuretics)
⩥ Which of the following conditions is most likely to cause
hyperkalemia?
A. Excessive vomiting
B. Insulin administration
C. Acute kidney injury
D. Hyperventilation. Answer: C. Acute kidney injury
⩥ What is the primary cause of lactic acidosis?
A. Excessive intake of dietary carbohydrates
B. Impaired oxygen delivery or utilization leading to anaerobic
metabolism
C. Hyperventilation
D. Renal reabsorption of lactic acid. Answer: B. Impaired oxygen
delivery or utilization leading to anaerobic metabolism
⩥ What is a key preanalytical factor that can falsely elevate potassium
levels in a sample?
A. Fasting before collection
PRACTICE FINAL EXAMINATION ACTUAL
QUESTIONS ASSESSMENT 2026 DETAILED
FIFTY QUESTIONS WITH VERY
ELABORATED CORRECTLY DEFINED
SOLUTIONS WELL ARRANGED GRADED A+
⩥ Why does hemolysis affect electrolyte measurement in blood
samples?
A. It dilutes plasma volume
B. It causes protein binding of electrolytes
C. It releases intracellular ions into the plasma or serum
D. It neutralizes all ions present. Answer: C. It releases intracellular ions
into the plasma or serum
⩥ Which of the following laboratory artifacts can result in falsely
elevated potassium readings?
A. Lipemia
B. Icterus
C. Hemolysis
D. Dehydration. Answer: C. Hemolysis
,⩥ Which electrolyte is most directly involved in maintaining the resting
membrane potential of cells?
A. Calcium
B. Potassium
C. Magnesium
D. Chloride. Answer: B. Potassium
⩥ The normal reference range for serum chloride is approximately:
A. 98-107 mmol/L
B. 75-90 mmol/L
C. 110-125 mmol/L
D. 60-70 mmol/L. Answer: A. 98-107 mmol/L
⩥ Which statement correctly matches the electrolyte with normal
reference range?
A. Calcium: 1.0-2.0 mmol/L
B. Potassium: 2.0-3.0 mmol/L
C. Sodium: 135-145 mmol/L
D. Magnesium: 0.2-0.5 mmol/L. Answer: C. Sodium: 135-145 mmol/L
⩥ Which form of an electrolyte is most important for immediate
physiological functions such as muscle contraction and nerve signaling?
A. Total
,B. Bound
C. Ionized
D. Excreted. Answer: C. Ionized
⩥ Why might total electrolyte levels not always reflect the
physiologically active portion of an electrolyte?
A. Total levels include electrolytes excreted in urine
B. Total levels exclude bound forms
C. Total levels include both bound and free forms, but only ionized
forms are active
D. Total levels only measure intracellular content. Answer: C. Total
levels include both bound and free forms, but only ionized forms are
active
⩥ Which of the following is a common cause of hyponatremia?
A. Dehydration due to water loss
B. Excessive water intake or syndrome of inappropriate antidiuretic
hormone secretion(SIADH)
C. Diabetes mellitus
D. Hyperaldosteronism. Answer: B. Excessive water intake or syndrome
of inappropriate antidiuretic hormone secretion(SIADH)
⩥ Which of the following is a common cause of hypokalemia?
A. Renal failure
, B. Diuretic use(e.g, loop or thiazide diuretics)
C. Addison's disease
D. Tissue breakdown. Answer: B. Diuretic use(e.g, loop or thiazide
diuretics)
⩥ Which of the following conditions is most likely to cause
hyperkalemia?
A. Excessive vomiting
B. Insulin administration
C. Acute kidney injury
D. Hyperventilation. Answer: C. Acute kidney injury
⩥ What is the primary cause of lactic acidosis?
A. Excessive intake of dietary carbohydrates
B. Impaired oxygen delivery or utilization leading to anaerobic
metabolism
C. Hyperventilation
D. Renal reabsorption of lactic acid. Answer: B. Impaired oxygen
delivery or utilization leading to anaerobic metabolism
⩥ What is a key preanalytical factor that can falsely elevate potassium
levels in a sample?
A. Fasting before collection
