ATI LPN
NCLEX PN Questions Respiratory System Questions
Question 1 of 5
Which of the following describes the Morphology of Emphysema:
Correct Answer: D
Rationale: All (D) describe emphysema morphology . Pale, voluminous lungs and alveolar thinning (50% loss) reflect air trapping . A, B, C are true individually. D's inclusivity unlike A's partiality captures full pathology, per document.
Question 2 of 5
Pulmonary surfactant:
Correct Answer: D
Rationale: Pulmonary surfactant prevents alveoli from collapsing (D) . Secreted by type II pneumocytes, it cuts surface tension (30 dynes/cm to 5), stabilizing 300 million alveoli (Page 1). Protection (A) is vague. Dust clearance (B) is ciliary. Bronchioles (C) don't produce it. D's role unlike B's ciliary action averts atelectasis, per document.
Question 3 of 5
Compared to a normal individual, a patient with idiopathic pulmonary fibrosis, one of the following is expected to be more than normal?
Correct Answer: B
Rationale: Idiopathic pulmonary fibrosis (IPF) raises pulmonary vascular resistance (B) via alveolar scarring. TLC (A) drops (~4 L vs. 6 L) due to restriction. FEV1 (C) decreases, but FEV1/FVC stays normal (Q1). PaO2 (D) falls (~60 mmHg) from diffusion impairment. B's increase capillary compression, hypoxic vasoconstriction strains the right heart (Q10), unlike A's or C's restrictive decline, per IPF pathology.
Question 4 of 5
Fick's law depend on multiple factors, which one of them will have the most effect when observing the diffusion of different gases?
Correct Answer: D
Rationale: Fick's law (diffusion rate = D × A × ΔP / d) ranks diffusion coefficient (D) highest for different gases (D) . D reflects gas solubility and molecular weight (Graham's law: D ∠1/√MW). CO2's D (0.57) exceeds O2's (0.024) 20-fold, despite O2's steeper gradient (A, ~60 mmHg vs. CO2's 6 mmHg). Distance (C, 0.2 μm) and area (A, 70 m^2) are constant; temperature (B) is stable (37°C). D's gas-specificity unlike A's universal drive dominates diffusion variance, per physiology (Q44).
Question 5 of 5
Which person would be expected to have the largest PAO2-PaO2 gradient?
Correct Answer: B
Rationale: Pulmonary fibrosis (B) maximizes PAO2-PaO2 gradient. Normal PAO2 ~100 mmHg, PaO2 ~95 mmHg (gradient ~5 mmHg); exercise (A) narrows it (perfusion rises). Fibrosis thickens diffusion barrier (0.2 to 1 μm), dropping PaO2 (~60 mmHg, Q10), widening gradient (~40 mmHg). Anemia (C) lowers O2 content, not gradient. Altitude (D) cuts both PAO2 and PaO2 (~60 mmHg), gradient ~5-10 mmHg. B's diffusion limit unlike A's efficiency drives the largest gap, per physiology (Q55).