BIO 168 – Human Physiology &
Pathophysiology Comprehensive Final
Exam 2026
1. Which transport mechanism moves water across a selectively permeable membrane due
to differences in solute concentration?
A. Facilitated diffusion
B. Active transport
C. Osmosis
D. Endocytosis
Answer: Osmosis
2. The primary ion responsible for the depolarization phase of a neuronal action potential
is:
A. Potassium
B. Calcium
C. Sodium
D. Chloride
Answer: Sodium
3. The sodium-potassium pump directly contributes to resting membrane potential by:
A. Moving 2 Na⁺ out and 3 K⁺ in
B. Moving 3 Na⁺ out and 2 K⁺ in
C. Allowing passive diffusion of Na⁺
D. Facilitating K⁺ entry only
Answer: Moving 3 Na⁺ out and 2 K⁺ in
4. During ventricular systole, which heart valves are open?
A. Mitral and tricuspid
B. Aortic and pulmonary
C. All four valves
D. None of the valves
Answer: Aortic and pulmonary
5. Cardiac output is calculated as:
A. Heart rate × blood pressure
B. Stroke volume × peripheral resistance
C. Heart rate × stroke volume
D. Blood volume × heart rate
Answer: Heart rate × stroke volume
6. The primary stimulus for erythropoietin release from the kidneys is:
A. Hyperglycemia
B. Low blood pressure
, C. Hypoxia
D. High iron levels
Answer: Hypoxia
7. Which structure of the nephron is primarily responsible for filtration?
A. Loop of Henle
B. Distal convoluted tubule
C. Glomerulus
D. Collecting duct
Answer: Glomerulus
8. Aldosterone increases blood pressure primarily by:
A. Promoting sodium and water reabsorption
B. Increasing potassium retention
C. Inhibiting renin release
D. Decreasing ADH secretion
Answer: Promoting sodium and water reabsorption
9. The primary driver of oxygen diffusion from alveoli into pulmonary capillaries is:
A. Active transport
B. Osmotic pressure
C. Partial pressure gradient
D. Surfactant secretion
Answer: Partial pressure gradient
10.Which hormone lowers blood glucose levels?
A. Glucagon
B. Cortisol
C. Insulin
D. Epinephrine
Answer: Insulin
11.The plateau phase of the cardiac action potential is largely due to:
A. Rapid potassium efflux
B. Sodium channel closure
C. Calcium influx
D. Chloride influx
Answer: Calcium influx
12.Which blood vessels have the greatest influence on systemic vascular resistance?
A. Arterioles
B. Veins
C. Capillaries
D. Venules
Answer: Arterioles
13.Hemoglobin’s affinity for oxygen decreases in the presence of:
A. High pH
B. Low carbon dioxide
C. Low temperature
, D. High carbon dioxide
Answer: High carbon dioxide
14.The primary pacemaker of the heart is the:
A. AV node
B. SA node
C. Bundle of His
D. Purkinje fibers
Answer: SA node
15.ADH increases water reabsorption in the:
A. Proximal convoluted tubule
B. Glomerulus
C. Loop of Henle
D. Collecting duct
Answer: Collecting duct
16.Which immune cells are primarily responsible for antibody production?
A. T helper cells
B. Cytotoxic T cells
C. B lymphocytes
D. Natural killer cells
Answer: B lymphocytes
17.During inspiration, the diaphragm:
A. Relaxes and moves upward
B. Contracts and moves downward
C. Relaxes and moves downward
D. Contracts and moves upward
Answer: Contracts and moves downward
18.Which electrolyte imbalance is most likely to cause cardiac arrhythmias?
A. Hypernatremia
B. Hypokalemia
C. Hypercalcemia
D. Hyperchloremia
Answer: Hypokalemia
19.The countercurrent multiplier system is located in the:
A. Distal tubule
B. Proximal tubule
C. Loop of Henle
D. Glomerular capsule
Answer: Loop of Henle
20.Which component of blood is primarily responsible for clot formation?
A. Erythrocytes
B. Leukocytes
C. Platelets
D. Plasma
Answer: Platelets
Pathophysiology Comprehensive Final
Exam 2026
1. Which transport mechanism moves water across a selectively permeable membrane due
to differences in solute concentration?
A. Facilitated diffusion
B. Active transport
C. Osmosis
D. Endocytosis
Answer: Osmosis
2. The primary ion responsible for the depolarization phase of a neuronal action potential
is:
A. Potassium
B. Calcium
C. Sodium
D. Chloride
Answer: Sodium
3. The sodium-potassium pump directly contributes to resting membrane potential by:
A. Moving 2 Na⁺ out and 3 K⁺ in
B. Moving 3 Na⁺ out and 2 K⁺ in
C. Allowing passive diffusion of Na⁺
D. Facilitating K⁺ entry only
Answer: Moving 3 Na⁺ out and 2 K⁺ in
4. During ventricular systole, which heart valves are open?
A. Mitral and tricuspid
B. Aortic and pulmonary
C. All four valves
D. None of the valves
Answer: Aortic and pulmonary
5. Cardiac output is calculated as:
A. Heart rate × blood pressure
B. Stroke volume × peripheral resistance
C. Heart rate × stroke volume
D. Blood volume × heart rate
Answer: Heart rate × stroke volume
6. The primary stimulus for erythropoietin release from the kidneys is:
A. Hyperglycemia
B. Low blood pressure
, C. Hypoxia
D. High iron levels
Answer: Hypoxia
7. Which structure of the nephron is primarily responsible for filtration?
A. Loop of Henle
B. Distal convoluted tubule
C. Glomerulus
D. Collecting duct
Answer: Glomerulus
8. Aldosterone increases blood pressure primarily by:
A. Promoting sodium and water reabsorption
B. Increasing potassium retention
C. Inhibiting renin release
D. Decreasing ADH secretion
Answer: Promoting sodium and water reabsorption
9. The primary driver of oxygen diffusion from alveoli into pulmonary capillaries is:
A. Active transport
B. Osmotic pressure
C. Partial pressure gradient
D. Surfactant secretion
Answer: Partial pressure gradient
10.Which hormone lowers blood glucose levels?
A. Glucagon
B. Cortisol
C. Insulin
D. Epinephrine
Answer: Insulin
11.The plateau phase of the cardiac action potential is largely due to:
A. Rapid potassium efflux
B. Sodium channel closure
C. Calcium influx
D. Chloride influx
Answer: Calcium influx
12.Which blood vessels have the greatest influence on systemic vascular resistance?
A. Arterioles
B. Veins
C. Capillaries
D. Venules
Answer: Arterioles
13.Hemoglobin’s affinity for oxygen decreases in the presence of:
A. High pH
B. Low carbon dioxide
C. Low temperature
, D. High carbon dioxide
Answer: High carbon dioxide
14.The primary pacemaker of the heart is the:
A. AV node
B. SA node
C. Bundle of His
D. Purkinje fibers
Answer: SA node
15.ADH increases water reabsorption in the:
A. Proximal convoluted tubule
B. Glomerulus
C. Loop of Henle
D. Collecting duct
Answer: Collecting duct
16.Which immune cells are primarily responsible for antibody production?
A. T helper cells
B. Cytotoxic T cells
C. B lymphocytes
D. Natural killer cells
Answer: B lymphocytes
17.During inspiration, the diaphragm:
A. Relaxes and moves upward
B. Contracts and moves downward
C. Relaxes and moves downward
D. Contracts and moves upward
Answer: Contracts and moves downward
18.Which electrolyte imbalance is most likely to cause cardiac arrhythmias?
A. Hypernatremia
B. Hypokalemia
C. Hypercalcemia
D. Hyperchloremia
Answer: Hypokalemia
19.The countercurrent multiplier system is located in the:
A. Distal tubule
B. Proximal tubule
C. Loop of Henle
D. Glomerular capsule
Answer: Loop of Henle
20.Which component of blood is primarily responsible for clot formation?
A. Erythrocytes
B. Leukocytes
C. Platelets
D. Plasma
Answer: Platelets
