Question 1

Which of the following statements best explains why muscle tissue contains more water than adipose tissue?

Accepted Answer

Muscle tissue is more metabolically active, requiring more water for chemical reactions.

Question 2

A patient with diabetes mellitus is experiencing polyuria. Which mechanism best explains this symptom?

Accepted Answer

Excess glucose in the urine draws water into the filtrate by osmosis, increasing urine output.

Question 3

Which hormone is released in response to high plasma osmolarity and acts to increase water reabsorption in the kidneys?

Accepted Answer

Antidiuretic hormone (ADH)

Question 4

If a patient has hypoaldosteronism (Addison’s Disease), which of the following would most likely occur?

Accepted Answer

Huge loss of sodium and water in urine, leading to low blood pressure.

Question 5

Which equation correctly represents the conversion of carbon dioxide to bicarbonate in the blood?

Accepted Answer

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

Question 6

A patient presents with muscle tetany and low blood calcium levels. Which hormone is most likely elevated in this patient?

Accepted Answer

Parathyroid hormone (PTH)

Question 7

Which of the following best describes the effect of Atrial Natriuretic Peptide (ANP) on blood pressure?

Accepted Answer

ANP suppresses ADH, renin, and aldosterone, causing sodium and water loss and lowering blood pressure.

Question 8

Which buffer system is most effective in the intracellular fluid (ICF) and urine?

Accepted Answer

Phosphate buffer system: $$\mathrm{NaH_2PO_4 + Na_2HPO_4}$$

Question 9

A patient with respiratory acidosis is likely to have which of the following?

Accepted Answer

High blood CO2 due to hypoventilation

Question 10

Which of the following scenarios would most likely result in edema?

Accepted Answer

Outward hydrostatic pressure exceeding inward colloidal osmotic pressure, causing fluid to leak into interstitial fluid

Question 11

Which of the following is a consequence of metabolic acidosis?

Accepted Answer

Accumulation of fixed acids such as lactic acid and ketone bodies, or loss of $$\mathrm{$$HCO_3$$^-}$$

Question 12

Which of the following best describes the role of potassium ($$\mathrm{K^+}) in $$acid-base balance?

Accepted Answer

$$\mathrm{K^+}$$ acts as a buffer, shifting in the opposite direction of $$\mathrm{H^+}$$ ions during acid-base disturbances.

Question 13

Which of the following would most likely occur in the kidneys during metabolic alkalosis?

Accepted Answer

Increased reabsorption of $$\mathrm{H^+}$$ and excretion of $$\mathrm{$$HCO_3$$^-}$$

Question 14

Which hormone increases sodium and water retention, and is also associated with higher blood glucose and osmolarity?

Accepted Answer

Glucocorticoids

Question 15

An elderly patient is more prone to dehydration than a young adult. Which factor contributes most to this increased risk?

Accepted Answer

Lower water reserves due to decreased muscle mass

Question 16

Which of the following best describes the effect of estrogen on fluid and electrolyte balance?

Accepted Answer

Estrogen increases sodium and water retention.

Question 17

A patient with congestive heart failure develops edema in the extremities. Which mechanism is most likely responsible?

Accepted Answer

Increased hydrostatic pressure in capillaries causes fluid to move into interstitial spaces.

Question 18

Which of the following is a real-life example of a buffer system acting in the body to resist changes in pH?

Accepted Answer

The carbonic acid-bicarbonate system neutralizes excess acid in the extracellular fluid.

Question 19

Which of the following would most likely occur if plasma osmolarity increases significantly?

Accepted Answer

The thirst center in the hypothalamus is stimulated, increasing water intake.

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

Study Guide - Practice Questions