Electrolyte Imbalances Exam
Questions And Correct
Answers (Verified Answers)
Plus Rationales 2025/2026
Q&A
1. Which electrolyte is primarily responsible for maintaining resting
membrane potential in cells?
A. Calcium
B. Sodium
C. Potassium
D. Magnesium
Potassium is the main intracellular cation and plays a key role in
maintaining the resting membrane potential of cells.
2. A patient presents with muscle weakness, constipation, and
hyporeflexia. Which electrolyte imbalance is most likely?
A. Hypernatremia
B. Hypokalemia
C. Hypercalcemia
D. Hypomagnesemia
B. Hypokalemia
Low potassium levels reduce neuromuscular excitability, causing
muscle weakness and constipation.
,3. Hypernatremia is defined as a serum sodium level greater than:
A. 135 mEq/L
B. 140 mEq/L
C. 145 mEq/L
D. 150 mEq/L
Normal sodium is 135–145 mEq/L; hypernatremia is >145 mEq/L and
indicates water deficit relative to sodium.
4. Which of the following can cause hyperkalemia?
A. Diuretic therapy
B. Acidosis
C. Vomiting
D. Hypoaldosteronism
B. Acidosis
Acidosis causes potassium to shift out of cells into the blood, raising
serum potassium levels.
5. What is a common ECG finding in hypokalemia?
A. Peaked T waves
B. Widened QRS
C. Flattened T waves with U waves
D. Shortened PR interval
Hypokalemia typically causes flattened T waves and the appearance
of U waves on ECG.
,6. Which electrolyte imbalance is most likely to cause tetany,
positive Chvostek’s sign, and Trousseau’s sign?
A. Hyperkalemia
B. Hypocalcemia
C. Hypermagnesemia
D. Hypernatremia
Low calcium increases neuromuscular excitability, leading to tetany
and positive Chvostek’s/Trousseau’s signs.
7. Which condition is commonly associated with hypercalcemia?
A. Chronic kidney disease
B. Hyperparathyroidism
C. Diuretic use
D. Addison’s disease
Hyperparathyroidism increases calcium resorption from bone, leading
to hypercalcemia.
8. A patient with diarrhea presents with weakness and low blood
pressure. What electrolyte imbalance is most likely?
A. Hyperkalemia
B. Hypokalemia
C. Hypernatremia
D. Hypercalcemia
Diarrhea causes potassium loss, leading to hypokalemia and
associated symptoms.
9. Magnesium plays a critical role in:
, A. Thyroid hormone synthesis
B. Neuromuscular conduction
C. Oxygen transport
D. Platelet aggregation
Magnesium is essential for proper neuromuscular function and acts
as a cofactor for many enzymes.
10. Which of the following can cause hyponatremia?
A. Diabetes insipidus
B. SIADH
C. Hyperaldosteronism
D. Excessive sweating
SIADH (Syndrome of Inappropriate Antidiuretic Hormone) leads to
water retention and dilutional hyponatremia.
11. What is the primary treatment for severe symptomatic
hyperkalemia?
A. Loop diuretics
B. IV calcium gluconate
C. Sodium bicarbonate
D. Oral potassium supplements
Calcium gluconate stabilizes cardiac membranes and reduces the risk
of arrhythmias in severe hyperkalemia.
12. Which electrolyte is mainly regulated by aldosterone?
A. Sodium
B. Potassium
Questions And Correct
Answers (Verified Answers)
Plus Rationales 2025/2026
Q&A
1. Which electrolyte is primarily responsible for maintaining resting
membrane potential in cells?
A. Calcium
B. Sodium
C. Potassium
D. Magnesium
Potassium is the main intracellular cation and plays a key role in
maintaining the resting membrane potential of cells.
2. A patient presents with muscle weakness, constipation, and
hyporeflexia. Which electrolyte imbalance is most likely?
A. Hypernatremia
B. Hypokalemia
C. Hypercalcemia
D. Hypomagnesemia
B. Hypokalemia
Low potassium levels reduce neuromuscular excitability, causing
muscle weakness and constipation.
,3. Hypernatremia is defined as a serum sodium level greater than:
A. 135 mEq/L
B. 140 mEq/L
C. 145 mEq/L
D. 150 mEq/L
Normal sodium is 135–145 mEq/L; hypernatremia is >145 mEq/L and
indicates water deficit relative to sodium.
4. Which of the following can cause hyperkalemia?
A. Diuretic therapy
B. Acidosis
C. Vomiting
D. Hypoaldosteronism
B. Acidosis
Acidosis causes potassium to shift out of cells into the blood, raising
serum potassium levels.
5. What is a common ECG finding in hypokalemia?
A. Peaked T waves
B. Widened QRS
C. Flattened T waves with U waves
D. Shortened PR interval
Hypokalemia typically causes flattened T waves and the appearance
of U waves on ECG.
,6. Which electrolyte imbalance is most likely to cause tetany,
positive Chvostek’s sign, and Trousseau’s sign?
A. Hyperkalemia
B. Hypocalcemia
C. Hypermagnesemia
D. Hypernatremia
Low calcium increases neuromuscular excitability, leading to tetany
and positive Chvostek’s/Trousseau’s signs.
7. Which condition is commonly associated with hypercalcemia?
A. Chronic kidney disease
B. Hyperparathyroidism
C. Diuretic use
D. Addison’s disease
Hyperparathyroidism increases calcium resorption from bone, leading
to hypercalcemia.
8. A patient with diarrhea presents with weakness and low blood
pressure. What electrolyte imbalance is most likely?
A. Hyperkalemia
B. Hypokalemia
C. Hypernatremia
D. Hypercalcemia
Diarrhea causes potassium loss, leading to hypokalemia and
associated symptoms.
9. Magnesium plays a critical role in:
, A. Thyroid hormone synthesis
B. Neuromuscular conduction
C. Oxygen transport
D. Platelet aggregation
Magnesium is essential for proper neuromuscular function and acts
as a cofactor for many enzymes.
10. Which of the following can cause hyponatremia?
A. Diabetes insipidus
B. SIADH
C. Hyperaldosteronism
D. Excessive sweating
SIADH (Syndrome of Inappropriate Antidiuretic Hormone) leads to
water retention and dilutional hyponatremia.
11. What is the primary treatment for severe symptomatic
hyperkalemia?
A. Loop diuretics
B. IV calcium gluconate
C. Sodium bicarbonate
D. Oral potassium supplements
Calcium gluconate stabilizes cardiac membranes and reduces the risk
of arrhythmias in severe hyperkalemia.
12. Which electrolyte is mainly regulated by aldosterone?
A. Sodium
B. Potassium
