Question 1

Which of the following best describes the principle of mass balance as it applies to fluid and electrolyte homeostasis?

Accepted Answer

The amount of water and electrolytes gained by the body must equal the amount lost.

Question 2

A patient presents with severe dehydration. Which of the following changes would you expect in their extracellular fluid (ECF)?

Accepted Answer

Decreased ECF volume and increased ECF osmolarity.

Question 3

Which equation represents the carbonic acid-bicarbonate buffer system in blood?

Accepted Answer

$$\mathrm{CO_2$ + H_2O \leftrightarrow H_2CO_3 \leftrightarrow $$HCO_3$$^- + H^+}$$

Question 4

A cell placed in a hypotonic extracellular solution will:

Accepted Answer

Swells as water enters the cell by osmosis.

Question 5

Which hormone is primarily responsible for increasing water reabsorption in the kidneys by inserting aquaporins into the distal tubule and collecting duct?

Accepted Answer

Antidiuretic hormone (ADH)

Question 6

A patient with hyperkalemia is at risk for which of the following cellular changes?

Accepted Answer

Resting membrane potential becomes more positive, impairing excitable cell function.

Question 7

Which of the following is a consequence of overhydration (hypotonic hydration)?

Accepted Answer

Cells swell due to water entering by osmosis.

Question 8

Which equation best describes the relationship between pH and hydrogen ion concentration?

Accepted Answer

$$\mathrm{pH = -\log_{10}[H^+]}$$

Question 9

A patient with metabolic acidosis due to diabetic ketoacidosis will likely exhibit which compensatory response?

Accepted Answer

Hyperventilation to decrease CO2 and raise blood pH.

Question 10

Which of the following best explains why sodium ion concentration is critical for fluid balance?

Accepted Answer

Sodium creates osmotic gradients that drive water reabsorption in the kidneys.

Question 11

Which hormone decreases sodium and water reabsorption in the kidneys, promoting natriuresis?

Accepted Answer

Atrial natriuretic peptide (ANP)

Question 12

A patient with hypocalcemia is likely to experience which of the following effects?

Accepted Answer

Neurons become hyperexcitable due to increased Na+ permeability.

Question 13

Which of the following is a major source of metabolic acids in the body?

Accepted Answer

Carbon dioxide ($$\mathrm{CO_2$}) $$produced during glucose metabolism

Question 14

Which of the following best describes the effect of respiratory acidosis on arterial blood gases (ABGs)?

Accepted Answer

Elevated $$\mathrm{$$PCO_2$$}$$ and decreased pH

Question 15

Which of the following mechanisms is used by the kidneys to compensate for acidosis?

Accepted Answer

Reabsorption of all available bicarbonate ions and secretion of hydrogen ions

Question 16

A patient with prolonged vomiting is at risk for which acid-base imbalance?

Accepted Answer

Metabolic alkalosis due to loss of hydrogen ions

Question 17

Which of the following is a function of water in the body?

Accepted Answer

Distributes body heat, cushions organs, and lubricates tissues

Question 18

Which of the following best describes the effect of aldosterone on electrolyte balance?

Accepted Answer

Increases sodium reabsorption and potassium secretion in the kidneys

Question 19

Which of the following buffer systems is most important in resisting changes in blood pH?

Accepted Answer

Carbonic acid-bicarbonate buffer system

Question 20

A patient with blood loss (hypovolemia) will experience which of the following changes in fluid compartments?

Accepted Answer

Equal loss of water and solutes, with no change in tonicity between ECF and cytosol

Fluid, Electrolyte, and Acid-Base Homeostasis: Study Notes

Study Guide - Practice Questions

Study Guide - Flashcards