ATI LPN
Questions for the Respiratory System Questions
Question 1 of 5
The lungs are attached to the walls of the thorax by means of the:
Correct Answer: B
Rationale: The parietal pleural membrane (B) attaches lungs to the thorax . This serous layer lines the chest wall, adhering via negative pressure (-5 mmHg) to the visceral pleura (C), encasing lungs. The pericardium (A) surrounds the heart, not lungs. Mesentery (D) supports abdominal organs. B's pleural linkage unlike A's cardiac or D's digestive role maintains lung position during breathing's 500 mL tidal shifts, per physiology (Page 1).
Question 2 of 5
A 12 years-old boy has a severe asthmatic attack with wheezing. His arterial pO2 is 60 mmHg and pCO2 is 30 mmHg. His:
Correct Answer: D
Rationale: In asthma, hypoxemia (PaO2 60 mmHg) drives hyperventilation, lowering PCO2 to 30 mmHg (D) . Normal PCO2 is 35-45 mmHg; here, it's below due to increased respiratory rate (RR > 15/min). FEV1/FVC decreases (A, false) in obstruction (< 70%, Q46). V/Q drops (B, false) in affected areas ventilation falls more than perfusion. PCO2 isn't high (C, false) gas exchange favors CO2 loss. D's hypocapnia unlike A's spirometry error reflects chemoreceptor response to low O2, boosting Va (e.g., 5-7 L/min), per asthma physiology.
Question 3 of 5
Vital capacity is defined as?
Correct Answer: D
Rationale: Vital capacity (VC) is IRV + Vt + ERV (~4.8 L). All volumes (A) include RV, making TLC (~6 L). Vt + RV (B) is ~1.7 L, not VC. IRV + ERV (C) omits Vt (~3.8 L). D's sum IRV (~3 L), Vt (~0.5 L), ERV (~1.3 L) is max exhale, measurable by spirometry, unlike A's total or B's partial, per lung volume definitions (Q14).
Question 4 of 5
One of the following is true regarding FRC?
Correct Answer: C
Rationale: At FRC, intra-alveolar pressure equals atmospheric . FRC (~2.5 L) is lung resting volume (A, true) and thorax's (B, true), but query seeks one. Alveolar pressure is 0 mmHg (760 mmHg) at rest (C), with intrapleural at -5 cm H2O (D, false). Compliance isn't lowest (E, false maximal, Q37). C's equilibrium unlike D's pressure error defines FRC's no-flow state, per physiology (Q2).
Question 5 of 5
Which of the following is FALSE concerning airway resistance (R)?
Correct Answer: A
Rationale: Later airway generations don't increase total resistance (A, false). Resistance (R ∠1/r^4) peaks in medium airways (bronchi), not terminal bronchioles total cross-sectional area (~70 m^2) cuts R in alveoli (Q16). Large airways dominate normally (B, true). High R lowers FEV1/FVC (C, true, Q8). Elasticity loss and constriction (D, true) raise R (e.g., COPD, asthma). A's error unlike B's norm misreads airflow dynamics, per physiology.