ADN Exam Questions With Answers and detailed Rationales
Question 1.
Which of the following is the primary intracellular cation responsible for maintaining cell
excitability and electrical conduction?
A. Sodium
B. Potassium
C. Calcium
D. Magnesium
Correct Answer: B. Potassium
Explanation: Potassium is the major cation of the intracellular fluid (ICF), whereas sodium
is the major cation of the extracellular fluid (ECF).
Question 2.
A patient presents with a serum sodium level of 128 mEq/L. Which clinical manifestation
should the nurse monitor for most closely?
A. Extreme thirst
B. Peripheral edema
C. Dry mucous membranes
D. Confusion and seizures
Correct Answer: D. Confusion and seizures
Explanation: Hyponatremia (sodium < 135 mEq/L) leads to cellular swelling, particularly
in the brain, which causes neurological symptoms like confusion and seizures.
Question 3.
A nurse is caring for a patient with a potassium level of 6.2 mEq/L. Which EKG change is
most characteristic of this imbalance?
A. Presence of U waves
B. Flattened T waves
C. Tall, peaked T waves
D. ST segment depression
Correct Answer: C. Tall, peaked T waves
Explanation: Hyperkalemia causes peaked T waves and widened QRS complexes, which
are medical emergencies due to the risk of cardiac arrest.
, Question 4.
Which IV solution is considered hypotonic and is used to treat cellular dehydration?
A. 0.9% Normal Saline
B. 0.45% Normal Saline
C. Lactated Ringer’s
D. 5% Dextrose in Normal Saline
Correct Answer: B. 0.45% Normal Saline
Explanation: 0.45% NS is hypotonic, meaning it has a lower osmolality than plasma,
causing fluid to shift from the ECF into the cells.
Question 5.
The nurse notes a positive Chvostek’s sign in a patient post-thyroidectomy. Which
electrolyte imbalance does this indicate?
A. Hypocalcemia
B. Hyperkalemia
C. Hyponatremia
D. Hypomagnesemia
Correct Answer: A. Hypocalcemia
Explanation: Chvostek’s sign (facial twitching) and Trousseau’s sign (carpal spasm) are
classic indicators of hypocalcemia or hypomagnesemia.
Question 6.
Which process describes the movement of water from an area of low solute concentration
to an area of high solute concentration?
A. Diffusion
B. Osmosis
C. Filtration
D. Active Transport
Correct Answer: B. Osmosis
Explanation: Osmosis is specifically the movement of water across a semipermeable
membrane based on concentration gradients.
Question 7.
A patient’s ABG results are: pH 7.30, PaCO2 52 mmHg, HCO3 24 mEq/L. How should the
nurse interpret these results?
A. Metabolic Acidosis
B. Metabolic Alkalosis
C. Respiratory Acidosis
D. Respiratory Alkalosis
Correct Answer: C. Respiratory Acidosis
Question 1.
Which of the following is the primary intracellular cation responsible for maintaining cell
excitability and electrical conduction?
A. Sodium
B. Potassium
C. Calcium
D. Magnesium
Correct Answer: B. Potassium
Explanation: Potassium is the major cation of the intracellular fluid (ICF), whereas sodium
is the major cation of the extracellular fluid (ECF).
Question 2.
A patient presents with a serum sodium level of 128 mEq/L. Which clinical manifestation
should the nurse monitor for most closely?
A. Extreme thirst
B. Peripheral edema
C. Dry mucous membranes
D. Confusion and seizures
Correct Answer: D. Confusion and seizures
Explanation: Hyponatremia (sodium < 135 mEq/L) leads to cellular swelling, particularly
in the brain, which causes neurological symptoms like confusion and seizures.
Question 3.
A nurse is caring for a patient with a potassium level of 6.2 mEq/L. Which EKG change is
most characteristic of this imbalance?
A. Presence of U waves
B. Flattened T waves
C. Tall, peaked T waves
D. ST segment depression
Correct Answer: C. Tall, peaked T waves
Explanation: Hyperkalemia causes peaked T waves and widened QRS complexes, which
are medical emergencies due to the risk of cardiac arrest.
, Question 4.
Which IV solution is considered hypotonic and is used to treat cellular dehydration?
A. 0.9% Normal Saline
B. 0.45% Normal Saline
C. Lactated Ringer’s
D. 5% Dextrose in Normal Saline
Correct Answer: B. 0.45% Normal Saline
Explanation: 0.45% NS is hypotonic, meaning it has a lower osmolality than plasma,
causing fluid to shift from the ECF into the cells.
Question 5.
The nurse notes a positive Chvostek’s sign in a patient post-thyroidectomy. Which
electrolyte imbalance does this indicate?
A. Hypocalcemia
B. Hyperkalemia
C. Hyponatremia
D. Hypomagnesemia
Correct Answer: A. Hypocalcemia
Explanation: Chvostek’s sign (facial twitching) and Trousseau’s sign (carpal spasm) are
classic indicators of hypocalcemia or hypomagnesemia.
Question 6.
Which process describes the movement of water from an area of low solute concentration
to an area of high solute concentration?
A. Diffusion
B. Osmosis
C. Filtration
D. Active Transport
Correct Answer: B. Osmosis
Explanation: Osmosis is specifically the movement of water across a semipermeable
membrane based on concentration gradients.
Question 7.
A patient’s ABG results are: pH 7.30, PaCO2 52 mmHg, HCO3 24 mEq/L. How should the
nurse interpret these results?
A. Metabolic Acidosis
B. Metabolic Alkalosis
C. Respiratory Acidosis
D. Respiratory Alkalosis
Correct Answer: C. Respiratory Acidosis
