$$\text{Water Intake} = \text{Water Output}$$

$$\text{Osmotic Pressure} \propto [\text{Na}^+]_{ECF}$$

$$\text{Urine Output}_{min} = 500\ \text{ml}$$

Question 1

Which fluid compartment contains the largest proportion of total body water in a healthy adult?

Accepted Answer

Intracellular fluid (ICF)

Question 2

A patient presents with severe dehydration. Which of the following best describes the sequence of events that occur at the cellular level?

Accepted Answer

ECF osmotic pressure rises, water leaves cells, cells shrink

Question 3

Which equation best represents the relationship between water intake and output for maintaining hydration?

Accepted Answer

$$	ext{Water Intake} = 	ext{Water Output}$$

Question 4

Which of the following is the primary mechanism by which the hypothalamic thirst center is activated?

Accepted Answer

Increase in plasma osmolality

Question 5

A patient with renal insufficiency rapidly ingests a large volume of water. What is the most likely consequence?

Accepted Answer

Hyponatremia and cellular swelling

Question 6

Which hormone is released in response to increased blood pressure and acts to decrease blood volume by promoting sodium and water excretion?

Accepted Answer

Atrial natriuretic peptide (ANP)

Question 7

Which of the following best describes the effect of aldosterone on kidney tubules?

Accepted Answer

Increases Na+ reabsorption and increases K+ secretion

Question 8

Which equation best represents the osmotic effect of sodium in the extracellular fluid?

Accepted Answer

$$	ext{Osmotic Pressure} \propto [	ext{Na}^+]_{ECF}$$

Question 9

Which of the following is a consequence of hypoproteinemia in the blood?

Accepted Answer

Decreased colloid osmotic pressure and edema

Question 10

Which of the following statements about potassium balance is correct?

Accepted Answer

Potassium balance is primarily regulated by secretion in the cortical collecting ducts

Question 11

A patient with acidosis is likely to experience which change in potassium levels?

Accepted Answer

Increase in ECF potassium due to H+ shifting into cells

Question 12

Which of the following is NOT a source of water intake in the body?

Accepted Answer

Insensible losses

Question 13

Which equation best represents the minimum daily urine output required to excrete wastes?

Accepted Answer

$$	ext{Urine Output}_{min} = 500\ 	ext{ml}$$

Question 14

Which of the following best describes the effect of ADH on urine concentration?

Accepted Answer

Increased ADH leads to concentrated urine and increased body fluid volume

Question 15

Which of the following is a direct effect of atrial natriuretic peptide (ANP) on the kidneys?

Accepted Answer

Decreased Na+ reabsorption

Question 16

Which hormone increases sodium reabsorption and water retention during pregnancy?

Accepted Answer

Estrogen

Question 17

Which of the following best describes the movement of water between fluid compartments?

Accepted Answer

Water moves freely along osmotic gradients

Question 18

Which of the following is a consequence of hyperkalemia?

Accepted Answer

Depolarization and reduced excitability of excitable cells

Question 19

Which of the following is the major cation in the intracellular fluid?

Accepted Answer

K+

Question 20

Which of the following best describes the effect of glucocorticoids on fluid balance?

Accepted Answer

Increase Na+ reabsorption and promote edema

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

Study Guide - Practice Questions