Exam: Obstructive and Restrictive Lung Diseases
100 Questions with Answers and Rationales
SECTION A: Overview of Pulmonary Function and Assessment
(Questions 1-15)
1. The primary function of the respiratory system is:
A) Regulation of blood pressure
B) Gas exchange (oxygenation and carbon dioxide elimination)
C) Digestion of nutrients
D) Production of hormones
Correct Answer: B) Gas exchange (oxygenation and carbon
dioxide elimination)
Expert Rationale: The primary function of the respiratory system is
gas exchange—oxygenating blood by transferring oxygen from the
alveoli to the pulmonary capillaries and eliminating carbon dioxide
from the blood to the alveoli. This process is essential for cellular
respiration and maintaining acid-base balance .
2. A normal resting tidal volume in a healthy adult is
approximately:
A) 150 mL
B) 500 mL
,C) 1000 mL
D) 3000 mL
Correct Answer: B) 500 mL
Expert Rationale: Tidal volume (TV) is the amount of air inhaled or
exhaled during normal, quiet breathing. Normal tidal volume in a
healthy adult is approximately 500 mL (or 5-10 mL/kg). Minute
ventilation = TV × respiratory rate (approximately 6-8 L/min) .
3. Vital capacity (VC) is defined as:
A) Tidal volume + Inspiratory reserve volume
B) Tidal volume + Inspiratory reserve volume + Expiratory
reserve volume
C) Total lung capacity - Residual volume
D) Both B and C
Correct Answer: D) Both B and C
Expert Rationale: Vital capacity (VC) is the maximum amount of air
that can be exhaled after a maximum inspiration. It equals Tidal
volume + Inspiratory reserve volume + Expiratory reserve volume. It
also equals Total lung capacity - Residual volume. Normal VC is
approximately 4.5-5 L .
4. Residual volume (RV) is defined as:
A) Volume of air remaining in the lungs after a forced expiration
B) Volume of air inhaled during a normal breath
,C) Maximum volume of air that can be exhaled
D) Total volume of air in the lungs
Correct Answer: A) Volume of air remaining in the lungs after
a forced expiration
Expert Rationale: Residual volume (RV) is the volume of air
remaining in the lungs after a maximal forced expiration. It cannot
be measured by simple spirometry and prevents lung collapse
(atelectasis). Normal RV is approximately 1-1.2 L .
5. Forced expiratory volume in one second (FEV1) measures:
A) Total amount of air that can be exhaled
B) The volume of air exhaled in the first second of a forced
expiration
C) The total capacity of the lungs
D) The amount of air remaining in the lungs
Correct Answer: B) The volume of air exhaled in the first
second of a forced expiration
Expert Rationale: FEV1 is the volume of air exhaled in the first
second of a forced expiration. It is a key measure in pulmonary
function testing and is reduced in obstructive lung diseases
(asthma, COPD) due to airway resistance .
6. A normal FEV1/FVC ratio is approximately:
, A) 100%
B) >70-80%
C) 50-60%
D) <50%
Correct Answer: B) >70-80%
Expert Rationale: A normal FEV1/FVC ratio is >70-80%. A ratio
<70% is consistent with obstructive lung disease (airflow
limitation). In restrictive lung disease, the FEV1/FVC ratio is
normal or elevated (>80%) but both FEV1 and FVC are reduced .
7. Which of the following is characteristic of obstructive lung
disease?
A) Reduced FEV1/FVC ratio and hyperinflation
B) Normal FEV1/FVC ratio with reduced total lung capacity
C) Increased diffusion capacity
D) Normal lung volumes
Correct Answer: A) Reduced FEV1/FVC ratio and
hyperinflation
Expert Rationale: Obstructive lung diseases (asthma, COPD) are
characterized by airway obstruction, leading to a reduced
FEV1/FVC ratio (<70%), increased residual volume, and
hyperinflation (increased total lung capacity due to air trapping) .
8. Which of the following is characteristic of restrictive lung
disease?