Lung volumes MCQs With Answer

This concise, Student-friendly post on Lung volumes MCQs With Answer is tailored for B. Pharm students studying respiratory physiology and pulmonary function. It covers essential keywords such as lung volumes, spirometry, tidal volume, vital capacity, residual volume, total lung capacity, pulmonary function tests, and clinical interpretation. The content is designed to strengthen understanding of normal values, measurement techniques, factors affecting lung volumes, and differences between obstructive and restrictive patterns. Clear, focused explanations help pharmacy students link physiology to drug effects on respiration and patient assessment. Now let’s test your knowledge with 50 MCQs on this topic.

Q1. What does tidal volume (VT) represent in lung physiology?

• The volume of air moved during a normal, quiet breath
• The maximum volume exhaled after a deep inhalation
• The air remaining in lungs after maximal expiration
• The sum of all lung volumes

Correct Answer: The volume of air moved during a normal, quiet breath

Q2. Which lung volume cannot be measured by simple spirometry?

• Tidal volume (VT)
• Inspiratory capacity (IC)
• Residual volume (RV)
• Vital capacity (VC)

Correct Answer: Residual volume (RV)

Q3. What is the typical approximate value for total lung capacity (TLC) in a healthy adult male?

• ~2.5 liters
• ~4.0 liters
• ~6.0 liters
• ~8.0 liters

Correct Answer: ~6.0 liters

Q4. Which equation correctly relates lung volumes?

• TLC = IC + ERV
• VC = TLC + RV
• TLC = VC + RV
• RV = IC + VT

Correct Answer: TLC = VC + RV

Q5. What does functional residual capacity (FRC) equal?

• RV + ERV
• TLC − RV
• IC + ERV
• VC − VT

Correct Answer: RV + ERV

Q6. Which lung volume is defined as the maximum volume of air that can be inspired after a normal expiration?

• Inspiratory capacity (IC)
• Expiratory reserve volume (ERV)
• Tidal volume (VT)
• Residual volume (RV)

Correct Answer: Inspiratory capacity (IC)

Q7. Which clinical pattern typically shows a reduced TLC?

• Obstructive lung disease
• Restrictive lung disease
• Both obstructive and restrictive equally
• Normal aging only

Correct Answer: Restrictive lung disease

Q8. In obstructive diseases like COPD, which lung volume usually increases?

• Vital capacity (VC)
• Residual volume (RV)
• Tidal volume (VT)
• Inspiratory capacity (IC)

Correct Answer: Residual volume (RV)

Q9. Which parameter measured in spirometry best differentiates obstructive from restrictive disease?

• FEV1/FVC ratio
• Tidal volume (VT)
• Inspiratory capacity (IC)
• Residual volume (RV)

Correct Answer: FEV1/FVC ratio

Q10. What does FEV1 represent?

• Forced expiratory volume in 1 second
• Forced expiratory volume in full test
• Functional expiratory volume at rest
• Fractional expiratory ventilation

Correct Answer: Forced expiratory volume in 1 second

Q11. How is vital capacity (VC) defined?

• The volume of air remaining after normal expiration
• The maximum volume that can be inhaled from residual volume
• The total volume exhaled after maximal inhalation
• The air exchanged per minute during quiet breathing

Correct Answer: The total volume exhaled after maximal inhalation

Q12. Inspiratory reserve volume (IRV) is best described as:

• Air inhaled during normal breathing
• Additional air inhaled after a normal inspiration
• Air remaining after forced expiration
• Volume used for gas exchange only

Correct Answer: Additional air inhaled after a normal inspiration

Q13. What factor typically decreases lung compliance?

• Emphysema
• Pulmonary fibrosis
• Aging-related elastin loss
• Bronchodilator therapy

Correct Answer: Pulmonary fibrosis

Q14. Which measurement requires body plethysmography rather than simple spirometry?

• Forced vital capacity (FVC)
• Residual volume (RV)
• FEV1
• Respiratory rate

Correct Answer: Residual volume (RV)

Q15. Which lung volume increases with age due to loss of elastic recoil?

• Inspiratory capacity (IC)
• Residual volume (RV)
• Vital capacity (VC)
• Expiratory reserve volume (ERV)

Correct Answer: Residual volume (RV)

Q16. Which of the following best explains air trapping in obstructive disease?

• Reduced airway resistance
• Increased airway collapse during expiration
• Decreased residual volume
• Increased inspiratory muscle strength

Correct Answer: Increased airway collapse during expiration

Q17. What is the clinical significance of an increased RV/TLC ratio?

• Improved gas exchange
• Indicates air trapping or hyperinflation
• Sign of enhanced lung elasticity
• Normal finding in athletes

Correct Answer: Indicates air trapping or hyperinflation

Q18. Which intervention would most likely decrease FRC?

• Deep inspiration before spirometry
• Administration of bronchodilator
• General anesthesia with muscle relaxation
• Smoking cessation

Correct Answer: General anesthesia with muscle relaxation

Q19. Which gas law underlies measurement of lung volumes with helium dilution?

• Boyle’s law
• Charles’s law
• Dalton’s law
• Henry’s law

Correct Answer: Boyle’s law

Q20. Maximum voluntary ventilation (MVV) assesses:

• Static lung volumes only
• Dynamic ventilatory capacity over time
• Only residual volume
• Diffusion capacity across alveoli

Correct Answer: Dynamic ventilatory capacity over time

Q21. Which condition commonly shows increased TLC but reduced FEV1/FVC?

• Pulmonary fibrosis
• Obstructive emphysema
• Restrictive chest wall disease
• Neuromuscular weakness

Correct Answer: Obstructive emphysema

Q22. Inspiratory capacity (IC) equals which combination?

• Tidal volume + Expiratory reserve volume
• Tidal volume + Inspiratory reserve volume
• Residual volume + Expiratory reserve volume
• Vital capacity + Residual volume

Correct Answer: Tidal volume + Inspiratory reserve volume

Q23. Which statement about spirometry calibration is true?

• Calibration isn’t necessary for modern devices
• Daily calibration with a 3L syringe is standard practice
• Calibration only required yearly
• Calibration uses oxygen as reference gas

Correct Answer: Daily calibration with a 3L syringe is standard practice

Q24. Which of the following decreases in restrictive lung disease?

• TLC and VC
• RV only
• FEV1/FVC ratio
• Residual volume fraction

Correct Answer: TLC and VC

Q25. Which factor most increases diffusion limitation of oxygen?

• Thicker alveolar-capillary membrane
• Higher alveolar PO2
• Increased cardiac output
• Increased hemoglobin concentration

Correct Answer: Thicker alveolar-capillary membrane

Q26. Which value is most affected by patient effort during spirometry?

• Residual volume (RV)
• Forced vital capacity (FVC)
• TLC measured by plethysmography
• Static functional residual capacity

Correct Answer: Forced vital capacity (FVC)

Q27. Which pattern is suggested by reduced FVC with normal or increased FEV1/FVC?

• Obstructive disease
• Restrictive disease
• Upper airway obstruction
• Neuromuscular disease only

Correct Answer: Restrictive disease

Q28. What is the clinical relevance of measuring diffusion capacity for carbon monoxide (DLCO)?

• Assesses airway resistance only
• Estimates alveolar-capillary gas transfer
• Measures residual volume directly
• Determines respiratory rate

Correct Answer: Estimates alveolar-capillary gas transfer

Q29. Which drug class can acutely increase airway caliber and affect spirometry results?

• Beta-2 agonists
• ACE inhibitors
• Statins
• Opioids

Correct Answer: Beta-2 agonists

Q30. When comparing supine to upright position, what happens to FRC?

• FRC increases when supine
• FRC decreases when supine
• FRC unchanged by posture
• FRC equals TLC in supine

Correct Answer: FRC decreases when supine

Q31. What is the major physiological determinant of TLC?

• Chest wall tone and respiratory muscle strength
• Airway resistance only
• Diffusion capacity
• Alveolar gas composition

Correct Answer: Chest wall tone and respiratory muscle strength

Q32. Which measurement indicates small airway dysfunction earlier than FEV1?

• Maximal inspiratory pressure
• Mid-expiratory flow rates (FEF25-75%)
• Tidal volume
• Residual volume

Correct Answer: Mid-expiratory flow rates (FEF25-75%)

Q33. What is the effect of obesity on lung volumes?

• Increased TLC and VC
• Reduced FRC and ERV
• Increased RV exclusively
• No effect on lung volumes

Correct Answer: Reduced FRC and ERV

Q34. Which parameter is most useful to monitor bronchodilator response?

• Change in FEV1 post-bronchodilator
• Baseline residual volume
• Tidal volume during sleep
• Total lung capacity by plethysmography

Correct Answer: Change in FEV1 post-bronchodilator

Q35. Which technology is best for measuring thoracic gas volume including trapped gas?

• Helium dilution
• Body plethysmography
• Standard spirometry
• Pulse oximetry

Correct Answer: Body plethysmography

Q36. Which change is characteristic of emphysema?

• Decreased TLC and increased FEV1
• Increased TLC and increased RV
• Reduced RV/TLC ratio
• Improved DLCO

Correct Answer: Increased TLC and increased RV

Q37. Which term describes the largest volume of air that can be exhaled after a maximal inhalation?

• Expiratory reserve volume (ERV)
• Vital capacity (VC)
• Functional residual capacity (FRC)
• Residual volume (RV)

Correct Answer: Vital capacity (VC)

Q38. During pregnancy, how are maternal lung volumes typically affected?

• Marked decrease in TLC due to uterine pressure
• Small decrease in FRC, ERV; TLC largely preserved
• Large increase in RV and TLC
• No changes occur

Correct Answer: Small decrease in FRC, ERV; TLC largely preserved

Q39. Which physiologic change increases residual volume (RV)?

• Enhanced elastic recoil of lungs
• Airway obstruction and collapse
• Strenuous inspiratory muscle training
• Bronchodilation before testing

Correct Answer: Airway obstruction and collapse

Q40. Which index is calculated to assess obstructive severity and is age- and sex-dependent?

• TLC measurement
• Predicted FEV1 percentage (FEV1 % predicted)
• Minute ventilation at rest
• Inspiratory reserve volume

Correct Answer: Predicted FEV1 percentage (FEV1 % predicted)

Q41. Which of these reduces airway resistance and may increase flows?

• Cholinergic agonists
• Beta-2 adrenergic agonists
• Mucus hypersecretion
• Bronchoconstrictors

Correct Answer: Beta-2 adrenergic agonists

Q42. Which test would detect restrictive physiology even when spirometry is normal?

• Tidal breathing analysis
• Measurement of TLC by plethysmography
• Pulse oximetry
• Peak expiratory flow only

Correct Answer: Measurement of TLC by plethysmography

Q43. What happens to ERV during exercise?

• ERV increases significantly
• ERV decreases because VT increases into reserve
• ERV converts to RV
• ERV becomes equal to TLC

Correct Answer: ERV decreases because VT increases into reserve

Q44. Which parameter is least likely to change with bronchodilator in fixed airway obstruction?

• Peak expiratory flow
• FEV1
• FEV1/FVC ratio
• Residual volume if severe remodeling present

Correct Answer: Residual volume if severe remodeling present

Q45. What is the significance of an increased closing capacity relative to FRC?

• Improved ventilation at base of lung
• Small airways close during normal tidal breathing, causing V/Q mismatch
• Indicates enhanced elastic recoil
• Normal finding in young adults

Correct Answer: Small airways close during normal tidal breathing, causing V/Q mismatch

Q46. Which pharmacologic agent can reduce respiratory drive and alter measured ventilatory volumes?

• Inhaled corticosteroids
• Opioids
• Beta-2 agonists
• Antihistamines only

Correct Answer: Opioids

Q47. How does high altitude affect lung volumes acutely?

• Increases FRC due to hypoxic vasoconstriction
• Little change in static lung volumes but increases ventilation
• Markedly decreases TLC immediately
• Eliminates residual volume

Correct Answer: Little change in static lung volumes but increases ventilation

Q48. Which condition shows low DLCO along with hyperinflation?

• Asthma with good control
• Emphysema
• Pulmonary fibrosis
• Pure neuromuscular weakness

Correct Answer: Emphysema

Q49. What practical advice improves reproducibility of spirometry in outpatient testing?

• Allow patient to hold breath for 30 seconds before test
• Provide clear coaching and repeat best of three efforts
• Perform only a single forced expiration to save time
• Give no instructions to prevent bias

Correct Answer: Provide clear coaching and repeat best of three efforts

Q50. For B. Pharm students, why is mastery of lung volumes important?

• Only relevant for physiotherapists
• Essential for understanding drug effects on respiratory mechanics and dosing
• Irrelevant to drug development and clinical pharmacy
• Important solely for cardiology exams

Correct Answer: Essential for understanding drug effects on respiratory mechanics and dosing

G S Sachin

I am a Registered Pharmacist under the Pharmacy Act, 1948, and the founder of PharmacyFreak.com. I hold a Bachelor of Pharmacy degree from Rungta College of Pharmaceutical Science and Research. With a strong academic foundation and practical knowledge, I am committed to providing accurate, easy-to-understand content to support pharmacy students and professionals. My aim is to make complex pharmaceutical concepts accessible and useful for real-world application.

Mail- Sachin@pharmacyfreak.com