Respiratory Therapist Exam (NBRC)
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
Question 1
What is the primary function of the respiratory system?
A. Pump blood
B. Exchange oxygen and carbon dioxide
C. Digest food
D. Produce hormones
Correct Answer: B
Rationale: The respiratory system is responsible for gas exchange (O₂ in, CO₂ out).
Question 2
Which structure is part of the upper airway?
A. Trachea
B. Bronchi
C. Larynx
D. Alveoli
Correct Answer: C
Rationale: The larynx is part of the upper airway.
Question 3
What is the normal adult respiratory rate?
,A. 4–8 breaths/min
B. 8–10 breaths/min
C. 12–20 breaths/min
D. 25–35 breaths/min
Correct Answer: C
Rationale: Normal adult respiratory rate is 12–20 breaths per minute.
Question 4
Which gas is most important for cellular metabolism?
A. Nitrogen
B. Oxygen
C. Carbon dioxide
D. Helium
Correct Answer: B
Rationale: Oxygen is required for ATP production in cells.
Question 5
What is hypoxemia?
A. Low oxygen in blood
B. High oxygen in blood
C. Low CO₂ in blood
D. High CO₂ in blood
Correct Answer: A
Rationale: Hypoxemia means reduced oxygen in arterial blood.
Question 6
What does hypercapnia mean?
,A. Low oxygen
B. High carbon dioxide in blood
C. Low blood pressure
D. High oxygen in lungs
Correct Answer: B
Rationale: Hypercapnia is elevated CO₂ levels in blood.
Question 7
Which device delivers low-flow oxygen?
A. Venturi mask
B. Nasal cannula
C. Mechanical ventilator
D. Endotracheal tube
Correct Answer: B
Rationale: Nasal cannula is a low-flow oxygen device.
Question 8
What is the normal oxygen saturation range in healthy adults?
A. 60–70%
B. 75–85%
C. 95–100%
D. 85–90%
Correct Answer: C
Rationale: Normal SpO₂ is typically 95–100%.
Question 9
Which artery is commonly used for ABG sampling?
, A. Radial artery
B. Femoral vein
C. Jugular vein
D. Carotid vein
Correct Answer: A
Rationale: The radial artery is the preferred site for ABGs.
Question 10
What does an ABG measure?
A. Blood sugar
B. Oxygen and acid-base status
C. Blood clotting
D. Heart rate
Correct Answer: B
Rationale: ABGs assess oxygenation and acid-base balance.
Question 11
What is pH a measure of?
A. Oxygen level
B. Acidity or alkalinity
C. Blood pressure
D. CO₂ production
Correct Answer: B
Rationale: pH indicates acidity or alkalinity of blood.
Question 12
Normal arterial pH range is:
Questions and Correct Answers
(Verified Answers) Plus Rationales 2026
Q&A | Instant Download Pdf
Question 1
What is the primary function of the respiratory system?
A. Pump blood
B. Exchange oxygen and carbon dioxide
C. Digest food
D. Produce hormones
Correct Answer: B
Rationale: The respiratory system is responsible for gas exchange (O₂ in, CO₂ out).
Question 2
Which structure is part of the upper airway?
A. Trachea
B. Bronchi
C. Larynx
D. Alveoli
Correct Answer: C
Rationale: The larynx is part of the upper airway.
Question 3
What is the normal adult respiratory rate?
,A. 4–8 breaths/min
B. 8–10 breaths/min
C. 12–20 breaths/min
D. 25–35 breaths/min
Correct Answer: C
Rationale: Normal adult respiratory rate is 12–20 breaths per minute.
Question 4
Which gas is most important for cellular metabolism?
A. Nitrogen
B. Oxygen
C. Carbon dioxide
D. Helium
Correct Answer: B
Rationale: Oxygen is required for ATP production in cells.
Question 5
What is hypoxemia?
A. Low oxygen in blood
B. High oxygen in blood
C. Low CO₂ in blood
D. High CO₂ in blood
Correct Answer: A
Rationale: Hypoxemia means reduced oxygen in arterial blood.
Question 6
What does hypercapnia mean?
,A. Low oxygen
B. High carbon dioxide in blood
C. Low blood pressure
D. High oxygen in lungs
Correct Answer: B
Rationale: Hypercapnia is elevated CO₂ levels in blood.
Question 7
Which device delivers low-flow oxygen?
A. Venturi mask
B. Nasal cannula
C. Mechanical ventilator
D. Endotracheal tube
Correct Answer: B
Rationale: Nasal cannula is a low-flow oxygen device.
Question 8
What is the normal oxygen saturation range in healthy adults?
A. 60–70%
B. 75–85%
C. 95–100%
D. 85–90%
Correct Answer: C
Rationale: Normal SpO₂ is typically 95–100%.
Question 9
Which artery is commonly used for ABG sampling?
, A. Radial artery
B. Femoral vein
C. Jugular vein
D. Carotid vein
Correct Answer: A
Rationale: The radial artery is the preferred site for ABGs.
Question 10
What does an ABG measure?
A. Blood sugar
B. Oxygen and acid-base status
C. Blood clotting
D. Heart rate
Correct Answer: B
Rationale: ABGs assess oxygenation and acid-base balance.
Question 11
What is pH a measure of?
A. Oxygen level
B. Acidity or alkalinity
C. Blood pressure
D. CO₂ production
Correct Answer: B
Rationale: pH indicates acidity or alkalinity of blood.
Question 12
Normal arterial pH range is:
