BIOL 252 Human Anatomy & Physiology II
w/Lab 2026 | Module 3 Respiratory
System |100+ Questions and Answers
with Rationales
1. What is the primary function of the respiratory system?
A. Produce red blood cells
B. Transport nutrients
C. Exchange oxygen and carbon dioxide
D. Filter blood
Answer: C. Exchange oxygen and carbon dioxide
Rationale: The respiratory system supplies oxygen to body tissues and
removes carbon dioxide, a metabolic waste product.
2. Which structure serves as the passageway for both air and food?
A. Larynx
B. Trachea
C. Pharynx
D. Bronchi
Answer: C. Pharynx
Rationale: The pharynx functions as a common passageway for both
the respiratory and digestive systems.
3. Which cartilage prevents food from entering the trachea during
swallowing?
,A. Thyroid cartilage
B. Cricoid cartilage
C. Arytenoid cartilage
D. Epiglottis
Answer: D. Epiglottis
Rationale: The epiglottis folds over the laryngeal opening during
swallowing to prevent aspiration.
4. The vocal cords are located in the:
A. Pharynx
B. Larynx
C. Trachea
D. Bronchi
Answer: B. Larynx
Rationale: The larynx contains the vocal folds responsible for sound
production.
5. Which structure is reinforced by C-shaped rings of hyaline
cartilage?
A. Bronchioles
B. Alveoli
C. Trachea
D. Pleura
Answer: C. Trachea
Rationale: Cartilage rings keep the trachea open while allowing the
esophagus to expand during swallowing.
,6. The smallest conducting airways are the:
A. Bronchi
B. Secondary bronchi
C. Bronchioles
D. Alveoli
Answer: C. Bronchioles
Rationale: Bronchioles are the smallest airways that conduct air
before reaching the respiratory zone.
7. Gas exchange primarily occurs in the:
A. Trachea
B. Bronchioles
C. Alveoli
D. Larynx
Answer: C. Alveoli
Rationale: Alveoli have thin walls and are surrounded by capillaries,
making them ideal for gas exchange.
8. Which cells produce pulmonary surfactant?
A. Type I alveolar cells
B. Type II alveolar cells
C. Macrophages
D. Goblet cells
Answer: B. Type II alveolar cells
Rationale: Type II cells secrete surfactant, reducing surface tension
and preventing alveolar collapse.
, 9. Pulmonary surfactant functions to:
A. Increase mucus production
B. Prevent alveolar collapse
C. Increase oxygen demand
D. Destroy pathogens
Answer: B. Prevent alveolar collapse
Rationale: Surfactant lowers surface tension, making lung expansion
easier.
10. Which muscle is primarily responsible for quiet inspiration?
A. Internal intercostals
B. Rectus abdominis
C. Diaphragm
D. Pectoralis major
Answer: C. Diaphragm
Rationale: The diaphragm contracts and flattens, increasing thoracic
volume during inspiration.
11. During inspiration, intrapulmonary pressure:
A. Increases above atmospheric pressure
B. Equals atmospheric pressure
C. Decreases below atmospheric pressure
D. Does not change
Answer: C. Decreases below atmospheric pressure
Rationale: Air flows into the lungs when intrapulmonary pressure falls
below atmospheric pressure.
w/Lab 2026 | Module 3 Respiratory
System |100+ Questions and Answers
with Rationales
1. What is the primary function of the respiratory system?
A. Produce red blood cells
B. Transport nutrients
C. Exchange oxygen and carbon dioxide
D. Filter blood
Answer: C. Exchange oxygen and carbon dioxide
Rationale: The respiratory system supplies oxygen to body tissues and
removes carbon dioxide, a metabolic waste product.
2. Which structure serves as the passageway for both air and food?
A. Larynx
B. Trachea
C. Pharynx
D. Bronchi
Answer: C. Pharynx
Rationale: The pharynx functions as a common passageway for both
the respiratory and digestive systems.
3. Which cartilage prevents food from entering the trachea during
swallowing?
,A. Thyroid cartilage
B. Cricoid cartilage
C. Arytenoid cartilage
D. Epiglottis
Answer: D. Epiglottis
Rationale: The epiglottis folds over the laryngeal opening during
swallowing to prevent aspiration.
4. The vocal cords are located in the:
A. Pharynx
B. Larynx
C. Trachea
D. Bronchi
Answer: B. Larynx
Rationale: The larynx contains the vocal folds responsible for sound
production.
5. Which structure is reinforced by C-shaped rings of hyaline
cartilage?
A. Bronchioles
B. Alveoli
C. Trachea
D. Pleura
Answer: C. Trachea
Rationale: Cartilage rings keep the trachea open while allowing the
esophagus to expand during swallowing.
,6. The smallest conducting airways are the:
A. Bronchi
B. Secondary bronchi
C. Bronchioles
D. Alveoli
Answer: C. Bronchioles
Rationale: Bronchioles are the smallest airways that conduct air
before reaching the respiratory zone.
7. Gas exchange primarily occurs in the:
A. Trachea
B. Bronchioles
C. Alveoli
D. Larynx
Answer: C. Alveoli
Rationale: Alveoli have thin walls and are surrounded by capillaries,
making them ideal for gas exchange.
8. Which cells produce pulmonary surfactant?
A. Type I alveolar cells
B. Type II alveolar cells
C. Macrophages
D. Goblet cells
Answer: B. Type II alveolar cells
Rationale: Type II cells secrete surfactant, reducing surface tension
and preventing alveolar collapse.
, 9. Pulmonary surfactant functions to:
A. Increase mucus production
B. Prevent alveolar collapse
C. Increase oxygen demand
D. Destroy pathogens
Answer: B. Prevent alveolar collapse
Rationale: Surfactant lowers surface tension, making lung expansion
easier.
10. Which muscle is primarily responsible for quiet inspiration?
A. Internal intercostals
B. Rectus abdominis
C. Diaphragm
D. Pectoralis major
Answer: C. Diaphragm
Rationale: The diaphragm contracts and flattens, increasing thoracic
volume during inspiration.
11. During inspiration, intrapulmonary pressure:
A. Increases above atmospheric pressure
B. Equals atmospheric pressure
C. Decreases below atmospheric pressure
D. Does not change
Answer: C. Decreases below atmospheric pressure
Rationale: Air flows into the lungs when intrapulmonary pressure falls
below atmospheric pressure.
