BIOL 271 MODULE 4: RESPIRATORY
PATHOPHYSIOLOGY EXAM
QUESTIONS AND ANSWERS
1. A patient presents with a V/Q ratio of 0. Which of the following best describes this
physiological state?
A. Dead space ventilation
B. Physiologic dead space
C. Normal gas exchange
D. Alveolar shunting
Answer: D
Conceptual Explanation: A V/Q ratio of 0 occurs when there is perfusion but no
ventilation (V=0), which is termed a shunt. Dead space occurs when there is ventilation but
no perfusion (V/Q = infinity).
2. In the pathogenesis of Emphysema, which enzyme is primarily responsible for the
destruction of alveolar walls?
A. Alpha-1 antitrypsin
,B. Lactate dehydrogenase
C. Elastase
D. Angiotensin-converting enzyme
Answer: C
Conceptual Explanation: Emphysema involves the breakdown of elastin in alveolar septa
by proteases like elastase, often released by neutrophils during inflammation.
3. Which clinical manifestation is a hallmark sign of a tension pneumothorax?
A. Mediastinal shift toward the contralateral side
B. Inward movement of the chest wall during inspiration
C. Decreased heart rate and hypertension
D. Hyper-resonance on the unaffected side
Answer: A
Conceptual Explanation: In a tension pneumothorax, air pressure builds up in the pleural
space, pushing the mediastinum and trachea toward the opposite (unaffected) side.
4. The late-phase response of an asthma attack is primarily mediated by the recruitment of
which cell type?
A. Mast cells
B. Natural Killer cells
, C. Eosinophils
D. Erythrocytes
Answer: C
Conceptual Explanation: While mast cells mediate the immediate IgE response, the late-
phase (4-8 hours later) involves eosinophils and other inflammatory cells causing further
airway damage.
5. Which genetic mutation is responsible for the dysfunction of the chloride channel in Cystic
Fibrosis?
A. BRCA1
B. CFTR
C. TP53
D. HER2
Answer: B
Conceptual Explanation: Cystic Fibrosis is caused by mutations in the Cystic Fibrosis
Transmembrane Conductance Regulator (CFTR) gene on chromosome 7.
6. Which of the following describes the pathophysiology of Acute Respiratory Distress
Syndrome (ARDS)?
A. Increased pulmonary capillary hydrostatic pressure
B. Excessive production of surfactant by Type II pneumocytes
PATHOPHYSIOLOGY EXAM
QUESTIONS AND ANSWERS
1. A patient presents with a V/Q ratio of 0. Which of the following best describes this
physiological state?
A. Dead space ventilation
B. Physiologic dead space
C. Normal gas exchange
D. Alveolar shunting
Answer: D
Conceptual Explanation: A V/Q ratio of 0 occurs when there is perfusion but no
ventilation (V=0), which is termed a shunt. Dead space occurs when there is ventilation but
no perfusion (V/Q = infinity).
2. In the pathogenesis of Emphysema, which enzyme is primarily responsible for the
destruction of alveolar walls?
A. Alpha-1 antitrypsin
,B. Lactate dehydrogenase
C. Elastase
D. Angiotensin-converting enzyme
Answer: C
Conceptual Explanation: Emphysema involves the breakdown of elastin in alveolar septa
by proteases like elastase, often released by neutrophils during inflammation.
3. Which clinical manifestation is a hallmark sign of a tension pneumothorax?
A. Mediastinal shift toward the contralateral side
B. Inward movement of the chest wall during inspiration
C. Decreased heart rate and hypertension
D. Hyper-resonance on the unaffected side
Answer: A
Conceptual Explanation: In a tension pneumothorax, air pressure builds up in the pleural
space, pushing the mediastinum and trachea toward the opposite (unaffected) side.
4. The late-phase response of an asthma attack is primarily mediated by the recruitment of
which cell type?
A. Mast cells
B. Natural Killer cells
, C. Eosinophils
D. Erythrocytes
Answer: C
Conceptual Explanation: While mast cells mediate the immediate IgE response, the late-
phase (4-8 hours later) involves eosinophils and other inflammatory cells causing further
airway damage.
5. Which genetic mutation is responsible for the dysfunction of the chloride channel in Cystic
Fibrosis?
A. BRCA1
B. CFTR
C. TP53
D. HER2
Answer: B
Conceptual Explanation: Cystic Fibrosis is caused by mutations in the Cystic Fibrosis
Transmembrane Conductance Regulator (CFTR) gene on chromosome 7.
6. Which of the following describes the pathophysiology of Acute Respiratory Distress
Syndrome (ARDS)?
A. Increased pulmonary capillary hydrostatic pressure
B. Excessive production of surfactant by Type II pneumocytes
