BIOS 255 Anatomy and Physiology III Chamberlain College of
Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and
Correct Answer Rationales
About This Exam Bank
This comprehensive 148-question exam bank is designed to prepare candidates for BIOS 255 Anatomy and
Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2 Comprehensive
Examination 100 Verified Questions and Correct Answer Rationales. Every question is aligned with the latest
official content outline and includes a detailed, evidence-based rationale, an explanation of why each remaining
option is incorrect, and a supporting reference.
Keywords
BIOS 255 Anatomy and Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and Correct Answer Rationales, exam bank, practice questions,
verified answers, detailed rationales, test prep, study guide, review questions, certification exam, latest update,
BIOS 255 Anatomy and Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and Correct Answer Rationales, exam bank, practice questions,
verified answers, detailed rationales
PART 1: ANALYZE THE INTEGRATED FUNCTION OF MAJOR ORGAN SYSTEMS IN
MAINTAINING HOMEOSTASIS
1. A patient with severe heart failure exhibits elevated jugular venous pressure, hepatomegaly, and peripheral edema.
Which alteration in Starling forces best explains these findings?
A) Decreased capillary hydrostatic pressure
B) Increased capillary permeability
C) Increased capillary hydrostatic pressure
D) Decreased interstitial oncotic pressure
' Correct Answer: C
Rationale: In right heart failure, increased venous pressure raises capillary hydrostatic pressure, leading to fluid
extravasation and edema. Decreased capillary hydrostatic pressure would reduce edema, while increased
permeability is typical of inflammation, not heart failure. Decreased interstitial oncotic pressure would also reduce
edema.
2. Which statement accurately describes the role of surfactant in pulmonary function?
A) It increases surface tension to prevent alveolar collapse.
B) It decreases surface tension by disrupting hydrogen bonds between water molecules.
C) It is produced by type I alveolar cells.
D) It increases compliance by thickening the alveolar fluid layer.
' Correct Answer: B
Rationale: Surfactant, produced by type II alveolar cells, reduces surface tension by interfering with hydrogen
bonding among water molecules, thereby preventing alveolar collapse. It does not increase surface tension; it
decreases it. Type I cells are for gas exchange, not surfactant production.
Page 1
,3. A patient's lab results show pH 7.28, PaCO2 30 mmHg, and HCO3- 14 mEq/L. Which acid-base disturbance is
present?
A) Respiratory acidosis
B) Metabolic alkalosis
C) Metabolic acidosis with respiratory compensation
D) Respiratory alkalosis with metabolic compensation
' Correct Answer: C
Rationale: Low pH indicates acidosis; low HCO3- indicates metabolic origin; low PaCO2 indicates respiratory
compensation (hyperventilation). Respiratory acidosis would have high PaCO2; metabolic alkalosis would have high
pH and HCO3-. Respiratory alkalosis would have high pH.
4. Which renal mechanism is primarily responsible for concentrating urine?
A) Glomerular filtration rate autoregulation
B) Countercurrent multiplication in the loop of Henle
C) Active reabsorption of glucose in the proximal tubule
D) Passive reabsorption of water in the distal tubule
' Correct Answer: B
Rationale: The countercurrent multiplier system in the loop of Henle establishes a medullary osmotic gradient,
allowing water reabsorption in the collecting duct under ADH influence. GFR autoregulation maintains filtration but
doesn't concentrate urine. Glucose reabsorption is unrelated to concentration; distal tubule water reabsorption is
minimal without ADH.
5. A patient presents with muscle weakness, cardiac arrhythmias, and increased urine output. Lab findings: serum
K+ 2.8 mEq/L, pH 7.50. Which condition is most likely?
A) Metabolic acidosis with hyperkalemia
B) Metabolic alkalosis with hypokalemia
C) Respiratory acidosis with hypokalemia
D) Respiratory alkalosis with hyperkalemia
' Correct Answer: B
Rationale: Low K+ and high pH indicate hypokalemia and metabolic alkalosis, often due to vomiting or diuretics.
Symptoms like weakness and arrhythmias are consistent with hypokalemia. Other options have mismatched pH or
potassium levels.
6. Which hormone increases blood calcium levels by stimulating osteoclast activity and renal calcium reabsorption?
A) Calcitonin
B) Parathyroid hormone (PTH)
C) Insulin-like growth factor 1 (IGF-1)
D) Thyroid hormone
' Correct Answer: B
Rationale: PTH raises blood calcium by promoting osteoclast-mediated bone resorption, increasing renal calcium
reabsorption, and activating vitamin D. Calcitonin lowers blood calcium. IGF-1 and thyroid hormone do not
primarily regulate calcium homeostasis.
7. A patient with a spinal cord injury at T6 experiences a sudden onset of severe hypertension, bradycardia, and
sweating above the level of injury. Which phenomenon is occurring?
A) Spinal shock
B) Autonomic dysreflexia
C) Orthostatic hypotension
Page 2
, D) Neurogenic shock
' Correct Answer: B
Rationale: Autonomic dysreflexia is a life-threatening condition in spinal cord injuries above T6, triggered by
noxious stimuli below the injury, causing massive sympathetic discharge and hypertension. Spinal shock is acute
flaccid paralysis; orthostatic hypotension is drop in BP on standing; neurogenic shock is hypotension and
bradycardia due to loss of sympathetic tone.
8. Which statement about the enteric nervous system is correct?
A) It is entirely under voluntary control.
B) It can function independently of the central nervous system.
C) It only consists of the vagus nerve.
D) It primarily controls skeletal muscle activity.
' Correct Answer: B
Rationale: The enteric nervous system (ENS) is a complex network of neurons in the GI tract that can regulate
motility and secretion independently, though it receives modulatory input from the autonomic nervous system. It is
not under voluntary control, does not consist only of the vagus, and does not control skeletal muscle.
9. During the ovarian cycle, which event is directly triggered by the luteinizing hormone (LH) surge?
A) Follicular growth
B) Ovulation
C) Menstruation
D) Progesterone secretion by the corpus luteum
' Correct Answer: B
Rationale: The LH surge mid-cycle triggers ovulation, releasing the secondary oocyte. Follicular growth is
primarily FSH-driven; menstruation results from falling progesterone and estrogen; progesterone secretion by the
corpus luteum occurs after ovulation, stimulated by LH but not the surge itself.
10. A patient with chronic obstructive pulmonary disease (COPD) has a PaO2 of 55 mmHg and PaCO2 of 60
mmHg. Which respiratory pattern is typically observed?
A) Hyperventilation with respiratory alkalosis
B) Hypoventilation with respiratory acidosis
C) Hyperventilation with metabolic acidosis
D) Hypoventilation with metabolic alkalosis
' Correct Answer: B
Rationale: In COPD, impaired gas exchange leads to hypoventilation, causing CO2 retention (hypercapnia) and
respiratory acidosis. Hyperventilation would lower PaCO2, not elevate it. Metabolic disturbances are not primary in
this scenario.
11. During a voluntary breath held at total lung capacity, the diaphragm is maximally contracted. Which additional
muscle action is required to prevent passive exhalation at that instant?
A) Relaxation of the external intercostals with recruitment of the internal intercostals
B) Isometric contraction of the abdominal wall muscles against a closed glottis
C) Continued contraction of the external intercostals and accessory inspiratory muscles against elastic recoil
D) Closure of the glottis alone, which eliminates the need for muscular effort
' Correct Answer: C
Rationale: At total lung capacity, the elastic recoil of the lung and chest wall generates a strong expiratory force, so
maintaining the breath requires sustained contraction of the external intercostals and accessory inspiratory muscles
to oppose that recoil. Abdominal contraction (B) would assist exhalation, not prevent it, and internal intercostal
Page 3
, recruitment (A) is an expiratory pattern. Glottic closure (D) reduces airflow but does not by itself counteract the
elastic recoil force acting on the thorax.
12. A patient's spirometry shows a reduced FEV1/FVC ratio with an increased residual volume, yet the single-breath
diffusing capacity for carbon monoxide (DLCO) is elevated. Which pathophysiologic mechanism best explains this
combination?
A) Interstitial fibrosis reducing alveolar membrane surface area
B) Airway obstruction with preserved alveolar-capillary surface and increased pulmonary capillary blood volume
C) Respiratory muscle weakness reducing maximal inspiratory pressure
D) Decreased pulmonary capillary recruitment from pulmonary hypertension
' Correct Answer: B
Rationale: An obstructive pattern with air trapping (elevated residual volume) and an elevated DLCO is
characteristic of asthma or early emphysema with preserved alveolar surface and increased capillary blood volume
from hyperinflation. Fibrosis (A) produces a restrictive pattern with reduced DLCO, muscle weakness (C) reduces
volumes without obstruction, and pulmonary capillary loss (D) lowers DLCO.
13. Which change in the oxyhemoglobin dissociation curve would most improve tissue oxygen unloading during
intense skeletal muscle exercise, and why?
A) A left shift from alkalosis, increasing hemoglobin's oxygen affinity
B) A right shift from increased 2,3-BPG, PCO2, and temperature, decreasing hemoglobin's oxygen affinity
C) A left shift from hypothermia, enhancing oxygen release at the tissues
D) A right shift from decreased PCO2, increasing oxygen loading in the lungs
' Correct Answer: B
Rationale: Exercising muscle produces CO2, heat, and acidosis, and erythrocytes increase 2,3-BPG, all of which
shift the curve right and reduce hemoglobin oxygen affinity, enhancing unloading at tissues. Left shifts (A, C)
increase affinity and impair unloading, while a right shift from decreased PCO2 (D) is physiologically inconsistent
with exercising muscle.
14. A patient has a lesion destroying the dorsal respiratory group's connections to the phrenic motor nucleus but an
intact ventral respiratory group. Which breathing pattern is most likely?
A) Complete apnea requiring mechanical ventilation
B) Irregular, gasping respirations with preserved voluntary breath-holding
C) Loss of automatic rhythm generation with preserved voluntary control of breathing
D) Normal quiet breathing with loss of voluntary breath-holding only
' Correct Answer: C
Rationale: The dorsal respiratory group in the medulla generates the basic automatic rhythm, while voluntary
control descends from the cortex via separate corticospinal pathways. Disrupting DRG output to phrenic motor
neurons abolishes automatic breathing but spares voluntary control, producing the classic 'Ondine's curse' pattern.
Complete apnea (A) would require loss of both automatic and voluntary pathways, and gasping (B) reflects more
caudal pre-Bötzinger dysfunction.
15. In the countercurrent multiplier, which transport event at the thick ascending limb of the loop of Henle is
essential for establishing the medullary osmotic gradient?
A) Active Na+/K+/2Cl- cotransport with impermeability to water
B) Aquaporin-2 mediated water reabsorption under ADH influence
C) Passive NaCl reabsorption driven by the vasa recta
D) Urea recycling through UT-A1 transporters in the thin descending limb
' Correct Answer: A
Page 4
Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and
Correct Answer Rationales
About This Exam Bank
This comprehensive 148-question exam bank is designed to prepare candidates for BIOS 255 Anatomy and
Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2 Comprehensive
Examination 100 Verified Questions and Correct Answer Rationales. Every question is aligned with the latest
official content outline and includes a detailed, evidence-based rationale, an explanation of why each remaining
option is incorrect, and a supporting reference.
Keywords
BIOS 255 Anatomy and Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and Correct Answer Rationales, exam bank, practice questions,
verified answers, detailed rationales, test prep, study guide, review questions, certification exam, latest update,
BIOS 255 Anatomy and Physiology III Chamberlain College of Nursing Academic Year 2026/2027 Examination 2
Comprehensive Examination 100 Verified Questions and Correct Answer Rationales, exam bank, practice questions,
verified answers, detailed rationales
PART 1: ANALYZE THE INTEGRATED FUNCTION OF MAJOR ORGAN SYSTEMS IN
MAINTAINING HOMEOSTASIS
1. A patient with severe heart failure exhibits elevated jugular venous pressure, hepatomegaly, and peripheral edema.
Which alteration in Starling forces best explains these findings?
A) Decreased capillary hydrostatic pressure
B) Increased capillary permeability
C) Increased capillary hydrostatic pressure
D) Decreased interstitial oncotic pressure
' Correct Answer: C
Rationale: In right heart failure, increased venous pressure raises capillary hydrostatic pressure, leading to fluid
extravasation and edema. Decreased capillary hydrostatic pressure would reduce edema, while increased
permeability is typical of inflammation, not heart failure. Decreased interstitial oncotic pressure would also reduce
edema.
2. Which statement accurately describes the role of surfactant in pulmonary function?
A) It increases surface tension to prevent alveolar collapse.
B) It decreases surface tension by disrupting hydrogen bonds between water molecules.
C) It is produced by type I alveolar cells.
D) It increases compliance by thickening the alveolar fluid layer.
' Correct Answer: B
Rationale: Surfactant, produced by type II alveolar cells, reduces surface tension by interfering with hydrogen
bonding among water molecules, thereby preventing alveolar collapse. It does not increase surface tension; it
decreases it. Type I cells are for gas exchange, not surfactant production.
Page 1
,3. A patient's lab results show pH 7.28, PaCO2 30 mmHg, and HCO3- 14 mEq/L. Which acid-base disturbance is
present?
A) Respiratory acidosis
B) Metabolic alkalosis
C) Metabolic acidosis with respiratory compensation
D) Respiratory alkalosis with metabolic compensation
' Correct Answer: C
Rationale: Low pH indicates acidosis; low HCO3- indicates metabolic origin; low PaCO2 indicates respiratory
compensation (hyperventilation). Respiratory acidosis would have high PaCO2; metabolic alkalosis would have high
pH and HCO3-. Respiratory alkalosis would have high pH.
4. Which renal mechanism is primarily responsible for concentrating urine?
A) Glomerular filtration rate autoregulation
B) Countercurrent multiplication in the loop of Henle
C) Active reabsorption of glucose in the proximal tubule
D) Passive reabsorption of water in the distal tubule
' Correct Answer: B
Rationale: The countercurrent multiplier system in the loop of Henle establishes a medullary osmotic gradient,
allowing water reabsorption in the collecting duct under ADH influence. GFR autoregulation maintains filtration but
doesn't concentrate urine. Glucose reabsorption is unrelated to concentration; distal tubule water reabsorption is
minimal without ADH.
5. A patient presents with muscle weakness, cardiac arrhythmias, and increased urine output. Lab findings: serum
K+ 2.8 mEq/L, pH 7.50. Which condition is most likely?
A) Metabolic acidosis with hyperkalemia
B) Metabolic alkalosis with hypokalemia
C) Respiratory acidosis with hypokalemia
D) Respiratory alkalosis with hyperkalemia
' Correct Answer: B
Rationale: Low K+ and high pH indicate hypokalemia and metabolic alkalosis, often due to vomiting or diuretics.
Symptoms like weakness and arrhythmias are consistent with hypokalemia. Other options have mismatched pH or
potassium levels.
6. Which hormone increases blood calcium levels by stimulating osteoclast activity and renal calcium reabsorption?
A) Calcitonin
B) Parathyroid hormone (PTH)
C) Insulin-like growth factor 1 (IGF-1)
D) Thyroid hormone
' Correct Answer: B
Rationale: PTH raises blood calcium by promoting osteoclast-mediated bone resorption, increasing renal calcium
reabsorption, and activating vitamin D. Calcitonin lowers blood calcium. IGF-1 and thyroid hormone do not
primarily regulate calcium homeostasis.
7. A patient with a spinal cord injury at T6 experiences a sudden onset of severe hypertension, bradycardia, and
sweating above the level of injury. Which phenomenon is occurring?
A) Spinal shock
B) Autonomic dysreflexia
C) Orthostatic hypotension
Page 2
, D) Neurogenic shock
' Correct Answer: B
Rationale: Autonomic dysreflexia is a life-threatening condition in spinal cord injuries above T6, triggered by
noxious stimuli below the injury, causing massive sympathetic discharge and hypertension. Spinal shock is acute
flaccid paralysis; orthostatic hypotension is drop in BP on standing; neurogenic shock is hypotension and
bradycardia due to loss of sympathetic tone.
8. Which statement about the enteric nervous system is correct?
A) It is entirely under voluntary control.
B) It can function independently of the central nervous system.
C) It only consists of the vagus nerve.
D) It primarily controls skeletal muscle activity.
' Correct Answer: B
Rationale: The enteric nervous system (ENS) is a complex network of neurons in the GI tract that can regulate
motility and secretion independently, though it receives modulatory input from the autonomic nervous system. It is
not under voluntary control, does not consist only of the vagus, and does not control skeletal muscle.
9. During the ovarian cycle, which event is directly triggered by the luteinizing hormone (LH) surge?
A) Follicular growth
B) Ovulation
C) Menstruation
D) Progesterone secretion by the corpus luteum
' Correct Answer: B
Rationale: The LH surge mid-cycle triggers ovulation, releasing the secondary oocyte. Follicular growth is
primarily FSH-driven; menstruation results from falling progesterone and estrogen; progesterone secretion by the
corpus luteum occurs after ovulation, stimulated by LH but not the surge itself.
10. A patient with chronic obstructive pulmonary disease (COPD) has a PaO2 of 55 mmHg and PaCO2 of 60
mmHg. Which respiratory pattern is typically observed?
A) Hyperventilation with respiratory alkalosis
B) Hypoventilation with respiratory acidosis
C) Hyperventilation with metabolic acidosis
D) Hypoventilation with metabolic alkalosis
' Correct Answer: B
Rationale: In COPD, impaired gas exchange leads to hypoventilation, causing CO2 retention (hypercapnia) and
respiratory acidosis. Hyperventilation would lower PaCO2, not elevate it. Metabolic disturbances are not primary in
this scenario.
11. During a voluntary breath held at total lung capacity, the diaphragm is maximally contracted. Which additional
muscle action is required to prevent passive exhalation at that instant?
A) Relaxation of the external intercostals with recruitment of the internal intercostals
B) Isometric contraction of the abdominal wall muscles against a closed glottis
C) Continued contraction of the external intercostals and accessory inspiratory muscles against elastic recoil
D) Closure of the glottis alone, which eliminates the need for muscular effort
' Correct Answer: C
Rationale: At total lung capacity, the elastic recoil of the lung and chest wall generates a strong expiratory force, so
maintaining the breath requires sustained contraction of the external intercostals and accessory inspiratory muscles
to oppose that recoil. Abdominal contraction (B) would assist exhalation, not prevent it, and internal intercostal
Page 3
, recruitment (A) is an expiratory pattern. Glottic closure (D) reduces airflow but does not by itself counteract the
elastic recoil force acting on the thorax.
12. A patient's spirometry shows a reduced FEV1/FVC ratio with an increased residual volume, yet the single-breath
diffusing capacity for carbon monoxide (DLCO) is elevated. Which pathophysiologic mechanism best explains this
combination?
A) Interstitial fibrosis reducing alveolar membrane surface area
B) Airway obstruction with preserved alveolar-capillary surface and increased pulmonary capillary blood volume
C) Respiratory muscle weakness reducing maximal inspiratory pressure
D) Decreased pulmonary capillary recruitment from pulmonary hypertension
' Correct Answer: B
Rationale: An obstructive pattern with air trapping (elevated residual volume) and an elevated DLCO is
characteristic of asthma or early emphysema with preserved alveolar surface and increased capillary blood volume
from hyperinflation. Fibrosis (A) produces a restrictive pattern with reduced DLCO, muscle weakness (C) reduces
volumes without obstruction, and pulmonary capillary loss (D) lowers DLCO.
13. Which change in the oxyhemoglobin dissociation curve would most improve tissue oxygen unloading during
intense skeletal muscle exercise, and why?
A) A left shift from alkalosis, increasing hemoglobin's oxygen affinity
B) A right shift from increased 2,3-BPG, PCO2, and temperature, decreasing hemoglobin's oxygen affinity
C) A left shift from hypothermia, enhancing oxygen release at the tissues
D) A right shift from decreased PCO2, increasing oxygen loading in the lungs
' Correct Answer: B
Rationale: Exercising muscle produces CO2, heat, and acidosis, and erythrocytes increase 2,3-BPG, all of which
shift the curve right and reduce hemoglobin oxygen affinity, enhancing unloading at tissues. Left shifts (A, C)
increase affinity and impair unloading, while a right shift from decreased PCO2 (D) is physiologically inconsistent
with exercising muscle.
14. A patient has a lesion destroying the dorsal respiratory group's connections to the phrenic motor nucleus but an
intact ventral respiratory group. Which breathing pattern is most likely?
A) Complete apnea requiring mechanical ventilation
B) Irregular, gasping respirations with preserved voluntary breath-holding
C) Loss of automatic rhythm generation with preserved voluntary control of breathing
D) Normal quiet breathing with loss of voluntary breath-holding only
' Correct Answer: C
Rationale: The dorsal respiratory group in the medulla generates the basic automatic rhythm, while voluntary
control descends from the cortex via separate corticospinal pathways. Disrupting DRG output to phrenic motor
neurons abolishes automatic breathing but spares voluntary control, producing the classic 'Ondine's curse' pattern.
Complete apnea (A) would require loss of both automatic and voluntary pathways, and gasping (B) reflects more
caudal pre-Bötzinger dysfunction.
15. In the countercurrent multiplier, which transport event at the thick ascending limb of the loop of Henle is
essential for establishing the medullary osmotic gradient?
A) Active Na+/K+/2Cl- cotransport with impermeability to water
B) Aquaporin-2 mediated water reabsorption under ADH influence
C) Passive NaCl reabsorption driven by the vasa recta
D) Urea recycling through UT-A1 transporters in the thin descending limb
' Correct Answer: A
Page 4
