NR 226: Fundamentals of Patient Care - Week 4: Fluid, Electrolyte &
Acid-Base Balance 2026 |Chamberlain
1. Which fluid compartment contains approximately two-thirds of the total
body water in adults?
A. Extracellular fluid (ECF)
B. Interstitial fluid
C. Intracellular fluid (ICF)
D. Intravascular fluid
Answer: C
Rationale: Intracellular fluid (ICF) makes up about two-thirds of the total body water,
while extracellular fluid (ECF) makes up the remaining one-third.
2. The movement of water across a semipermeable membrane from an area of
lower solute concentration to an area of higher solute concentration is called:
A. Diffusion
B. Active transport
C. Filtration
D. Osmosis
Answer: D
Rationale: Osmosis is specifically the movement of water based on concentration
gradients, whereas diffusion refers to the movement of solutes.
,3. Which process involves the use of energy (ATP) to move electrolytes across
cell membranes against a concentration gradient?
A. Active transport
B. Filtration
C. Osmosis
D. Diffusion
Answer: A
Rationale: Active transport requires energy (ATP) to move substances like the sodium-
potassium pump against their concentration gradients.
4. A patient presents with a serum sodium level of 150 mEq/L. Which term best
describes this condition?
A. Hypernatremia
B. Hyponatremia
C. Hypokalemia
D. Hyperkalemia
Answer: A
Rationale: The normal range for serum sodium is 135-145 mEq/L. A level of 150 mEq/L is
considered hypernatremia.
5. What is the primary regulator of fluid output in the healthy body?
A. The lungs
B. The skin
C. The kidneys
D. The gastrointestinal tract
Answer: C
Rationale: The kidneys are the primary organs for regulating fluid and electrolyte balance
by adjusting urine output based on the body’s needs.
, 6. Which hormone is released by the posterior pituitary gland to cause the
kidneys to reabsorb water, effectively decreasing urine output?
A. Antidiuretic hormone (ADH)
B. Aldosterone
C. Atrial natriuretic peptide (ANP)
D. Renin
Answer: A
Rationale: ADH (vasopressin) signals the kidneys to retain water to maintain blood
volume and osmolarity.
7. A patient’s ECG shows peaked T waves and a widened QRS complex. Which
electrolyte imbalance should the nurse suspect?
A. Hyperkalemia
B. Hypokalemia
C. Hypocalcemia
D. Hypercalcemia
Answer: A
Rationale: Hyperkalemia (high potassium) causes characteristic ECG changes, including
tall peaked T waves and dangerous cardiac arrhythmias.
8. Which clinical sign is a classic indicator of hypocalcemia?
A. Negative Romberg sign
B. Hypernatremia
C. Decreased deep tendon reflexes
D. Positive Chvostek’s sign
Answer: D
Rationale: Chvostek’s sign (facial twitching when tapping the facial nerve) and
Trousseau’s sign are classic indicators of hypocalcemia.
Acid-Base Balance 2026 |Chamberlain
1. Which fluid compartment contains approximately two-thirds of the total
body water in adults?
A. Extracellular fluid (ECF)
B. Interstitial fluid
C. Intracellular fluid (ICF)
D. Intravascular fluid
Answer: C
Rationale: Intracellular fluid (ICF) makes up about two-thirds of the total body water,
while extracellular fluid (ECF) makes up the remaining one-third.
2. The movement of water across a semipermeable membrane from an area of
lower solute concentration to an area of higher solute concentration is called:
A. Diffusion
B. Active transport
C. Filtration
D. Osmosis
Answer: D
Rationale: Osmosis is specifically the movement of water based on concentration
gradients, whereas diffusion refers to the movement of solutes.
,3. Which process involves the use of energy (ATP) to move electrolytes across
cell membranes against a concentration gradient?
A. Active transport
B. Filtration
C. Osmosis
D. Diffusion
Answer: A
Rationale: Active transport requires energy (ATP) to move substances like the sodium-
potassium pump against their concentration gradients.
4. A patient presents with a serum sodium level of 150 mEq/L. Which term best
describes this condition?
A. Hypernatremia
B. Hyponatremia
C. Hypokalemia
D. Hyperkalemia
Answer: A
Rationale: The normal range for serum sodium is 135-145 mEq/L. A level of 150 mEq/L is
considered hypernatremia.
5. What is the primary regulator of fluid output in the healthy body?
A. The lungs
B. The skin
C. The kidneys
D. The gastrointestinal tract
Answer: C
Rationale: The kidneys are the primary organs for regulating fluid and electrolyte balance
by adjusting urine output based on the body’s needs.
, 6. Which hormone is released by the posterior pituitary gland to cause the
kidneys to reabsorb water, effectively decreasing urine output?
A. Antidiuretic hormone (ADH)
B. Aldosterone
C. Atrial natriuretic peptide (ANP)
D. Renin
Answer: A
Rationale: ADH (vasopressin) signals the kidneys to retain water to maintain blood
volume and osmolarity.
7. A patient’s ECG shows peaked T waves and a widened QRS complex. Which
electrolyte imbalance should the nurse suspect?
A. Hyperkalemia
B. Hypokalemia
C. Hypocalcemia
D. Hypercalcemia
Answer: A
Rationale: Hyperkalemia (high potassium) causes characteristic ECG changes, including
tall peaked T waves and dangerous cardiac arrhythmias.
8. Which clinical sign is a classic indicator of hypocalcemia?
A. Negative Romberg sign
B. Hypernatremia
C. Decreased deep tendon reflexes
D. Positive Chvostek’s sign
Answer: D
Rationale: Chvostek’s sign (facial twitching when tapping the facial nerve) and
Trousseau’s sign are classic indicators of hypocalcemia.
