Question 1

Which of the following best describes the distribution of total body water in an average adult?

Accepted Answer

Intracellular fluid (ICF) contains about 2/3 of total body water, while extracellular fluid (ECF) contains about 1/3.

Question 2

A patient receives a rapid intravenous infusion of 1 liter of 3% NaCl solution. Which of the following best describes the expected shift in body fluid compartments?

Accepted Answer

Water will move from the intracellular fluid (ICF) to the extracellular fluid (ECF), causing cells to shrink.

Question 3

Which of the following is the major cation in the extracellular fluid (ECF)?

Accepted Answer

Na+

Question 4

A patient with severe diarrhea is found to have a serum sodium of 140 mmol/L and decreased ECF volume. Which type of dehydration is this?

Accepted Answer

Isosmotic dehydration

Question 5

Which hormone is released by the heart in response to overhydration and acts as a potent diuretic and natriuretic?

Accepted Answer

Atrial natriuretic peptide (ANP)

Question 6

Calculate the osmolarity of a 1 M solution of CaCl$$_2 in $$water. (Assume complete dissociation.)

Accepted Answer

$$3\ 	ext{Osm/L}$$

Question 7

A patient with small cell lung cancer develops confusion, hyponatremia, and low serum osmolality. Which hormone is most likely inappropriately elevated?

Accepted Answer

Antidiuretic hormone (ADH)

Question 8

Which of the following best explains why acidosis is associated with hypercalcemia?

Accepted Answer

Increased H$$^+$$ binds to albumin, displacing Ca$$^{2+}$$ and increasing free ionized Ca$$^{2+}.$$

Question 9

Which of the following laboratory values is considered normal for serum potassium (K$$^+) in $$adults?

Accepted Answer

$$3.5-5.5\ 	ext{mmol/L}$$

Question 10

A patient with Addison’s disease (adrenal insufficiency) is most likely to develop which type of dehydration?

Accepted Answer

Hyposmotic dehydration

Question 11

Which of the following best describes the effect of aldosterone on renal handling of sodium and potassium?

Accepted Answer

Increases Na$$^+$$ reabsorption and increases K$$^+$$ secretion

Question 12

Which of the following is the correct formula for calculating pH?

Accepted Answer

$$pH = -\log [H^+]$$

Question 13

A patient presents with muscle cramps, nausea, and confusion after running a marathon and drinking only water. Which electrolyte disturbance is most likely?

Accepted Answer

Hyponatremia

Question 14

Which of the following is a symptom of hypocalcemia?

Accepted Answer

Chvostek’s sign (facial muscle twitch with tapping)

Question 15

Which of the following best describes the difference between strong and weak acids?

Accepted Answer

Strong acids completely dissociate in solution; weak acids only partially dissociate.

Question 16

Which of the following is the primary buffer system in the extracellular fluid?

Accepted Answer

Bicarbonate buffer system

Question 17

A patient with chronic kidney disease develops hyperkalemia. Which of the following treatments would help lower serum potassium by shifting K$$^+$$ into cells?

Accepted Answer

Administration of insulin and glucose

Question 18

Which of the following best explains why water follows sodium in the body?

Accepted Answer

Osmosis causes water to move toward areas of higher Na$$^+$$ concentration.

Question 19

Which of the following is a likely cause of hypernatremia?

Accepted Answer

Diabetes insipidus

Question 20

Which of the following best describes the effect of parathyroid hormone (PTH) on calcium and phosphate handling in the kidney?

Accepted Answer

Increases Ca$$^{2+}$$ reabsorption and decreases PO$$_4$$^{3-}$$ reabsorption

Chapter 26: Fluid, Electrolyte, and Acid-Base Balance – Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards