BI
,OL331/BIOL 331 Module 5
Pathophysiology | Portage |Q&A| 26/27
1. A respiratory physiologist is studying the movement of air into and out of the alveoli. Which term
specifically describes this mechanical process?
A) Diffusion
B) Ventilation
C) Perfusion
D) Respiration
Correct Answer: Ventilation
Rationale: Ventilation is the mechanical flow of gases into and out of the alveoli. Diffusion is gas
exchange across the respiratory membrane, perfusion is blood flow in pulmonary capillaries, and
respiration encompasses cellular utilization of oxygen, making them incorrect for this specific
mechanical process.
2. During inspiration at rest, which muscle is the primary driver of air movement into the lungs?
A) External intercostals
B) Diaphragm
C) Internal intercostals
D) Abdominal muscles
,Correct Answer: Diaphragm
Rationale: The diaphragm is the principal muscle of inspiration, contracting and descending to create
negative intrathoracic pressure. External intercostals assist, internal intercostals aid forced expiration,
and abdominal muscles aid forced expiration, making them incorrect as the primary driver.
3. A student is examining the innervation of the primary muscle of respiration. Which nerve roots
provide motor innervation to the diaphragm?
A) T2 to T4
B) C3, C4, C5
C) L1 to L3
D) S1 to S2
Correct Answer: C3, C4, C5
Rationale: The phrenic nerve arises from cervical roots C3, C4, and C5 to innervate the diaphragm. T2-
T4 innervate intercostals, L1-L3 innervate lower abdominal muscles, and S1-S2 innervate pelvic
structures, making them incorrect.
4. During quiet breathing, which statement accurately describes the active and passive phases of the
respiratory cycle?
A) Both inspiration and expiration are active
B) Inspiration is active, expiration is passive at rest
, C) Inspiration is passive, expiration is active
D) Both inspiration and expiration are passive
Correct Answer: Inspiration is active, expiration is passive at rest
Rationale: At rest, inspiration requires active contraction of the diaphragm and external intercostals,
while expiration is passive due to elastic recoil. Active expiration occurs only during forced breathing,
making the other options incorrect descriptions of quiet breathing.
5. A researcher is studying the property that describes the ease with which the lungs can be inflated.
Which term is being examined?
A) Resistance
B) Compliance
C) Elasticity
D) Surface tension
Correct Answer: Compliance
Rationale: Compliance reflects the distensibility of lung tissue and the ease of inflation. Resistance
opposes airflow, elasticity is the recoil property, and surface tension is a force within alveoli, making
them incorrect for this description.
6. A patient with emphysema has destruction of alveolar walls. What effect does this have on lung
compliance?
A) Decreased compliance
,OL331/BIOL 331 Module 5
Pathophysiology | Portage |Q&A| 26/27
1. A respiratory physiologist is studying the movement of air into and out of the alveoli. Which term
specifically describes this mechanical process?
A) Diffusion
B) Ventilation
C) Perfusion
D) Respiration
Correct Answer: Ventilation
Rationale: Ventilation is the mechanical flow of gases into and out of the alveoli. Diffusion is gas
exchange across the respiratory membrane, perfusion is blood flow in pulmonary capillaries, and
respiration encompasses cellular utilization of oxygen, making them incorrect for this specific
mechanical process.
2. During inspiration at rest, which muscle is the primary driver of air movement into the lungs?
A) External intercostals
B) Diaphragm
C) Internal intercostals
D) Abdominal muscles
,Correct Answer: Diaphragm
Rationale: The diaphragm is the principal muscle of inspiration, contracting and descending to create
negative intrathoracic pressure. External intercostals assist, internal intercostals aid forced expiration,
and abdominal muscles aid forced expiration, making them incorrect as the primary driver.
3. A student is examining the innervation of the primary muscle of respiration. Which nerve roots
provide motor innervation to the diaphragm?
A) T2 to T4
B) C3, C4, C5
C) L1 to L3
D) S1 to S2
Correct Answer: C3, C4, C5
Rationale: The phrenic nerve arises from cervical roots C3, C4, and C5 to innervate the diaphragm. T2-
T4 innervate intercostals, L1-L3 innervate lower abdominal muscles, and S1-S2 innervate pelvic
structures, making them incorrect.
4. During quiet breathing, which statement accurately describes the active and passive phases of the
respiratory cycle?
A) Both inspiration and expiration are active
B) Inspiration is active, expiration is passive at rest
, C) Inspiration is passive, expiration is active
D) Both inspiration and expiration are passive
Correct Answer: Inspiration is active, expiration is passive at rest
Rationale: At rest, inspiration requires active contraction of the diaphragm and external intercostals,
while expiration is passive due to elastic recoil. Active expiration occurs only during forced breathing,
making the other options incorrect descriptions of quiet breathing.
5. A researcher is studying the property that describes the ease with which the lungs can be inflated.
Which term is being examined?
A) Resistance
B) Compliance
C) Elasticity
D) Surface tension
Correct Answer: Compliance
Rationale: Compliance reflects the distensibility of lung tissue and the ease of inflation. Resistance
opposes airflow, elasticity is the recoil property, and surface tension is a force within alveoli, making
them incorrect for this description.
6. A patient with emphysema has destruction of alveolar walls. What effect does this have on lung
compliance?
A) Decreased compliance
