NUR 631/NUR631 Final Exam V1 |
Advanced Physiology and Pathophysiology
Q&A with Rationale | Grand Canyon
University
1. What is the primary intracellular cation responsible for maintaining the resting membrane
potential?
A. Potassium
B. Sodium
C. Calcium
D. Magnesium
Answer: A
Rationale: Potassium is the major intracellular cation and is crucial for maintaining the
electrical gradient across cell membranes. A change in potassium concentration
significantly affects the resting membrane potential of excitable cells like neurons and
myocytes. This electrolyte balance is regulated primarily by the sodium-potassium pump.
2. Which hormone is released by the posterior pituitary in response to increased plasma
osmolality?
A. Antidiuretic Hormone (ADH)
B. Aldosterone
,C. Renin
D. Cortisol
Answer: A
Rationale: Antidiuretic Hormone (ADH), also known as vasopressin, is synthesized in the
hypothalamus and stored in the posterior pituitary. It is released when osmoreceptors
detect a rise in plasma osmolality or a decrease in blood volume. ADH acts on the renal
collecting ducts to increase water reabsorption, thereby concentrating the urine and
diluting the blood.
3. In the compensatory stage of shock, which mechanism helps maintain blood pressure?
A. Peripheral vasodilation
B. Activation of the Renin-Angiotensin-Aldosterone System (RAAS)
C. Activation of the parasympathetic nervous system
D. Decreased heart rate
Answer: B
Rationale: The RAAS is triggered by decreased renal perfusion during the early stages of
shock. Angiotensin II causes systemic vasoconstriction to elevate blood pressure while
aldosterone promotes sodium and water retention. These physiological responses aim to
preserve cardiac output and perfusion to vital organs.
, 4. A patient with chronic kidney disease (CKD) is most likely to develop which type of acid-
base imbalance?
A. Respiratory acidosis
B. Respiratory alkalosis
C. Metabolic alkalosis
D. Metabolic acidosis
Answer: D
Rationale: Metabolic acidosis occurs in CKD due to the kidney’s inability to excrete
hydrogen ions and regenerate bicarbonate. As nephrons are lost, the production of
ammonia for buffering also decreases. This leads to an accumulation of organic acids and a
drop in systemic pH.
5. Which type of hypersensitivity reaction is characterized by the production of IgE antibodies
and the release of histamine from mast cells?
A. Type IV
B. Type II
C. Type III
D. Type I
Answer: D
Advanced Physiology and Pathophysiology
Q&A with Rationale | Grand Canyon
University
1. What is the primary intracellular cation responsible for maintaining the resting membrane
potential?
A. Potassium
B. Sodium
C. Calcium
D. Magnesium
Answer: A
Rationale: Potassium is the major intracellular cation and is crucial for maintaining the
electrical gradient across cell membranes. A change in potassium concentration
significantly affects the resting membrane potential of excitable cells like neurons and
myocytes. This electrolyte balance is regulated primarily by the sodium-potassium pump.
2. Which hormone is released by the posterior pituitary in response to increased plasma
osmolality?
A. Antidiuretic Hormone (ADH)
B. Aldosterone
,C. Renin
D. Cortisol
Answer: A
Rationale: Antidiuretic Hormone (ADH), also known as vasopressin, is synthesized in the
hypothalamus and stored in the posterior pituitary. It is released when osmoreceptors
detect a rise in plasma osmolality or a decrease in blood volume. ADH acts on the renal
collecting ducts to increase water reabsorption, thereby concentrating the urine and
diluting the blood.
3. In the compensatory stage of shock, which mechanism helps maintain blood pressure?
A. Peripheral vasodilation
B. Activation of the Renin-Angiotensin-Aldosterone System (RAAS)
C. Activation of the parasympathetic nervous system
D. Decreased heart rate
Answer: B
Rationale: The RAAS is triggered by decreased renal perfusion during the early stages of
shock. Angiotensin II causes systemic vasoconstriction to elevate blood pressure while
aldosterone promotes sodium and water retention. These physiological responses aim to
preserve cardiac output and perfusion to vital organs.
, 4. A patient with chronic kidney disease (CKD) is most likely to develop which type of acid-
base imbalance?
A. Respiratory acidosis
B. Respiratory alkalosis
C. Metabolic alkalosis
D. Metabolic acidosis
Answer: D
Rationale: Metabolic acidosis occurs in CKD due to the kidney’s inability to excrete
hydrogen ions and regenerate bicarbonate. As nephrons are lost, the production of
ammonia for buffering also decreases. This leads to an accumulation of organic acids and a
drop in systemic pH.
5. Which type of hypersensitivity reaction is characterized by the production of IgE antibodies
and the release of histamine from mast cells?
A. Type IV
B. Type II
C. Type III
D. Type I
Answer: D
