All of the following pairings are correct (assuming normal person at rest) EXCEPT

Correct Answer: B

Rationale: Choice B (alveolar ventilation = 7500 ml) is incorrect. Tidal volume (TV) = 500 ml (choice A) is true for a resting adult. Alveolar ventilation (V̇A) = (TV - dead space) × respiratory rate; with TV = 500 ml, dead space = 150 ml, rate = 12/min, V̇A = (500 - 150) × 12 = 4200 ml/min, not 7500 ml/min (likely total ventilation, 500 × 15). Choice C (pulmonary blood flow = 5000 ml/min) matches cardiac output at rest. ' FRC is the volume post-normal expiration (ERV + RV, ≈ 2300 ml). Choice E (physiologic dead space = 150 ml) aligns with anatomic dead space in health. B's overestimation misrepresents alveolar gas exchange volume, making it the exception.

Correct Answer: C

Rationale: surfactant's phospholipid film forms via tubular myelin, a precursor from Type II pneumocytes. Choice A is false; phospholipids (e.g., DPPC) treat IRDS but need proteins (SP-B, SP-C) for full efficacy. Choice B is wrong; smoking reduces surfactant via oxidative damage. Choice D is true; IRDS results from surfactant deficiency, increasing tension and collapsing alveoli. Choice E is false; carbohydrates aid stability, but phospholipids dominate. Tubular myelin, rich in dipalmitoylphosphatidylcholine, reduces surface tension (Laplace's law: P = 2T/r), stabilizing alveoli. C accurately describes this process, critical for lung function.

Correct Answer: D

Rationale: peripheral chemoreceptors (carotid/aortic bodies) increase firing when POâ‚‚ drops below 100 mmHg (e.g., 60 mmHg threshold). Choice A is true; carotid bodies sense all three. Choice B is false; central response to pCOâ‚‚ dominates. Choice C is wrong; aortic bodies are in the arch, not valve. Choice E is false; they sense arterial POâ‚‚. D reflects their hypoxia sensitivity, critical for ventilation drive.

Correct Answer: D

Rationale: functional residual capacity (FRC) is the volume after normal expiration (ERV + RV, ≈2.4 L), not inspiration (FRC + TV = end-inspiratory volume). Choice A is true; tidal volume (TV, ≈500 mL) is normal breathing. ' vital capacity (VC, ≈4.8 L) is max inspiration to max expiration. Choice C is accurate; residual volume (RV, ≈1.2 L) remains after max expiration. FRC, the resting lung volume, balances chest wall and lung recoil, misstated in D as inspiratory, confusing it with inspiratory capacity or end-tidal volume. D's error makes it the incorrect definition.

Correct Answer: D

Rationale: halving radius (r) increases resistance (R) 16-fold per Poiseuille's law (R ∝ 1/r⁴). If r becomes r/2, R = 1/(r/2)⁴ = 16/r⁴. Choice A (2x) is linear. Choice B (4x) is r². Choice C (8x) is r³. Choice E (no effect) ignores physics. In airways (e.g., bronchoconstriction), small changes amplify resistance (e.g., 2 mm to 1 mm, R rises 16x), impacting flow significantly. D reflects this exponential relationship accurately.