D236 Pathophysiology: Fluid, Electrolyte & Acid-Base Imbalances
Practice Pack 2026 |WGU
1. Which process describes the movement of water from an area of lower solute
concentration to an area of higher solute concentration?
A. Diffusion
B. Active Transport
C. Filtration
D. Osmosis
Answer: D
Rationale: Osmosis is specifically the movement of water across a semi-permeable
membrane toward a higher concentration of solutes.
2. A patient is diagnosed with hypervolemia. Which clinical manifestation is
most likely to be observed?
A. Poor skin turgor
B. Tachycardia
C. Dry mucous membranes
D. Bounding pulse
Answer: D
Rationale: Hypervolemia (fluid volume excess) typically presents with a bounding pulse,
distended neck veins, and peripheral edema.
,3. Which hormone is primarily responsible for the reabsorption of sodium and
water in the kidneys?
A. Aldosterone
B. Atrial Natriuretic Peptide (ANP)
C. Antidiuretic Hormone (ADH)
D. Glucagon
Answer: A
Rationale: Aldosterone, secreted by the adrenal cortex, promotes sodium and water
retention and potassium excretion.
4. What is the primary intracellular cation in the human body?
A. Sodium
B. Magnesium
C. Calcium
D. Potassium
Answer: D
Rationale: Potassium is the major cation inside the cells, while sodium is the major cation
in the extracellular fluid.
5. A patient’s lab results show a serum sodium level of 128 mEq/L. Which
condition does this indicate?
A. Hyponatremia
B. Hypernatremia
C. Hypokalemia
D. Hyperkalemia
Answer: A
Rationale: Normal serum sodium is 135-145 mEq/L; a level of 128 mEq/L indicates
hyponatremia.
, 6. Which of the following EKG changes is most characteristic of hypokalemia?
A. Peaked T waves
B. Presence of U waves
C. Widened QRS complex
D. Shortened QT interval
Answer: B
Rationale: Hypokalemia often causes the development of U waves and flat or inverted T
waves on an EKG.
7. Chvostek’s sign and Trousseau’s sign are classic clinical indicators for which
imbalance?
A. Hypercalcemia
B. Hypernatremia
C. Hypocalcemia
D. Hypokalemia
Answer: C
Rationale: Hypocalcemia increases neuromuscular excitability, leading to these signs
(facial twitching and carpal spasms).
8. An arterial blood gas (ABG) result shows: pH 7.30, PaCO2 50 mmHg, and
HCO3 24 mEq/L. What is the interpretation?
A. Metabolic Acidosis
B. Respiratory Acidosis
C. Respiratory Alkalosis
D. Metabolic Alkalosis
Answer: B
Rationale: A low pH (<7.35) combined with a high PaCO2 (>45 mmHg) indicates
respiratory acidosis.
Practice Pack 2026 |WGU
1. Which process describes the movement of water from an area of lower solute
concentration to an area of higher solute concentration?
A. Diffusion
B. Active Transport
C. Filtration
D. Osmosis
Answer: D
Rationale: Osmosis is specifically the movement of water across a semi-permeable
membrane toward a higher concentration of solutes.
2. A patient is diagnosed with hypervolemia. Which clinical manifestation is
most likely to be observed?
A. Poor skin turgor
B. Tachycardia
C. Dry mucous membranes
D. Bounding pulse
Answer: D
Rationale: Hypervolemia (fluid volume excess) typically presents with a bounding pulse,
distended neck veins, and peripheral edema.
,3. Which hormone is primarily responsible for the reabsorption of sodium and
water in the kidneys?
A. Aldosterone
B. Atrial Natriuretic Peptide (ANP)
C. Antidiuretic Hormone (ADH)
D. Glucagon
Answer: A
Rationale: Aldosterone, secreted by the adrenal cortex, promotes sodium and water
retention and potassium excretion.
4. What is the primary intracellular cation in the human body?
A. Sodium
B. Magnesium
C. Calcium
D. Potassium
Answer: D
Rationale: Potassium is the major cation inside the cells, while sodium is the major cation
in the extracellular fluid.
5. A patient’s lab results show a serum sodium level of 128 mEq/L. Which
condition does this indicate?
A. Hyponatremia
B. Hypernatremia
C. Hypokalemia
D. Hyperkalemia
Answer: A
Rationale: Normal serum sodium is 135-145 mEq/L; a level of 128 mEq/L indicates
hyponatremia.
, 6. Which of the following EKG changes is most characteristic of hypokalemia?
A. Peaked T waves
B. Presence of U waves
C. Widened QRS complex
D. Shortened QT interval
Answer: B
Rationale: Hypokalemia often causes the development of U waves and flat or inverted T
waves on an EKG.
7. Chvostek’s sign and Trousseau’s sign are classic clinical indicators for which
imbalance?
A. Hypercalcemia
B. Hypernatremia
C. Hypocalcemia
D. Hypokalemia
Answer: C
Rationale: Hypocalcemia increases neuromuscular excitability, leading to these signs
(facial twitching and carpal spasms).
8. An arterial blood gas (ABG) result shows: pH 7.30, PaCO2 50 mmHg, and
HCO3 24 mEq/L. What is the interpretation?
A. Metabolic Acidosis
B. Respiratory Acidosis
C. Respiratory Alkalosis
D. Metabolic Alkalosis
Answer: B
Rationale: A low pH (<7.35) combined with a high PaCO2 (>45 mmHg) indicates
respiratory acidosis.
