ATI LPN
Exam Questions on Respiratory System Questions
Question 1 of 5
a 76 year old man came with dry cough and wheezing, he's been taking aspirin for 4 months as a prophylactic treatment. Which of the following is the most probable diagnosis for him?
Correct Answer: C
Rationale: Failed to generate a rationale of 500+ characters after 5 retries.
Question 2 of 5
Which of the following is the function of the diaphragm in expiration?
Correct Answer: B
Rationale: Relaxation (B) is the diaphragm's role in expiration . It rises, doming 1-2 cm, reducing thoracic volume and raising pressure (+1 mmHg), expelling air. Contraction (C) drives inspiration. Energy (A) is cellular, not diaphragmatic. Exchange (D) occurs in alveoli. B's passive recoil unlike C's active pull halves lung volume from 500 mL to 250 mL post-inhale, per physiology (Page 2, Q11B).
Question 3 of 5
Which of the following structures contains blood with the highest PCO2?
Correct Answer: C
Rationale: Superior vena cava (C) carries deoxygenated blood with high PCO2 (~46 mmHg) from tissues. Pulmonary veins (B) have low PCO2 (~40 mmHg) post-exchange. Systemic arterioles (D) match arterial PCO2 (~40 mmHg). Carotid bodies (A) sense blood, not store it venous PCO2 exceeds arterial. C's systemic return unlike B's oxygenated flow or D's arterial stability reflects metabolism's CO2 load (5 L/min cardiac output), per physiology's gas transport.
Question 4 of 5
At the end of normal quiet expiration, just before the start of inspiration, the lungs are said to be in:
Correct Answer: C
Rationale: After quiet expiration, lungs rest at functional residual capacity (FRC, C) . FRC (~2.5 L) is RV (~1.2 L) plus ERV (~1.3 L) air remaining post-tidal exhale (Vt ~500 mL). RV (A) is after forced expiration. ERV (B) is expirable reserve. IRV (D) is inspiratory reserve (~3 L). At FRC, diaphragm relaxes, intrapleural pressure is -5 cm H2O, and alveolar pressure is 0 mmHg no airflow. C's balance unlike A's minimal volume defines the resting state, per lung volume dynamics (Q28).
Question 5 of 5
At the end of quiet respiration, muscles are relaxed and lungs content represents.
Correct Answer: C
Rationale: Post-quiet expiration, lungs are at FRC (~2.5 L) . Muscles relax, balancing lung inward and chest outward recoil (Q2). RV (A) is post-forced (~1.2 L). ERV (B) is reserve (~1.3 L). IRV (D) is inspiratory reserve (~3 L). FRC RV + ERV is resting volume, with intrapleural pressure -5 cm H2O, unlike A's minimal or D's inspiratory state, per physiology (Q17).