ATI LPN
Questions for Respiratory System Questions
Question 1 of 5
Halving the radius of an airway increases resistance:
Correct Answer: D
Rationale: halving radius (r) increases resistance (R) 16-fold per Poiseuille's law (R ∠1/râ´). If r becomes r/2, R = 1/(r/2)â´ = 16/râ´. 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.
Question 2 of 5
Regarding the neural control of breathing, which statement is INCORRECT?
Correct Answer: D
Rationale: ventral respiratory group (VRG) neurons include expiratory cells that discharge spontaneously in forced breathing, not silent as stated. Choice A is true; centers and chemoreceptors are distinct. ' quiet expiration is passive (recoil). Choice C is accurate; inspiratory neurons (DRG) drive phrenic nerves. Choice E (12-15/min) fits. VRG's role in active expiration contradicts D's ‘no discharge,' making it false.
Question 3 of 5
Which of the following is NOT involved in the control of ventilation?
Correct Answer: C
Rationale: the basal ganglia regulate movement, not ventilation directly. Choice A (peripheral chemoreceptors) senses POâ‚‚/PCOâ‚‚/pH, driving breathing. Choice B (stretch receptors) modulates via Hering-Breuer reflex. Choice D (pons) refines rhythm (pneumotaxic center). Choice E (muscles) executes. The medulla (not listed) is primary, with pons and receptors integrating, but basal ganglia's role in motor disorders (e.g., Parkinson's) doesn't extend to respiratory control, making C the outsider.
Question 4 of 5
Which of the following substances is NOT removed from the blood by the lung?
Correct Answer: D
Rationale: adrenaline (epinephrine) passes through the lung largely unchanged, unlike other substances. Choice A (prostaglandins, e.g., PGEâ‚‚) is inactivated by 15-hydroxyprostaglandin dehydrogenase. Choice B (noradrenaline) is partially removed (less than serotonin). Choice C (acetylcholine) is hydrolyzed by cholinesterase. Choice E (bradykinin) is inactivated by ACE. The lung's metabolic role clears peptides, amines, and lipids, but catecholamines like adrenaline resist significant uptake or breakdown, maintaining systemic effects (e.g., fight-or-flight), making D the exception.
Question 5 of 5
The single most effective health promotion activity that a nurse could teach a group of community-dwelling senior citizens that would most likely help them prevent influenza and pneumonia would be which of the following?
Correct Answer: C
Rationale: The annual influenza vaccine is the most effective health promotion activity for preventing influenza and its complication, pneumonia, especially in senior citizens who are at higher risk due to age-related immune decline. The vaccine primes the immune system to recognize and fight specific flu strains, reducing infection risk by up to 60% when well-matched, and lowering severity if infected. Hand washing reduces transmission but doesn't provide direct immunity. Avoiding crowds limits exposure but isn't as proactive or reliable as vaccination. Exercise boosts general health but lacks the specific protective effect of the vaccine against flu viruses. For seniors, who face increased morbidity from flu and pneumonia, the nurse's focus on vaccination aligns with public health priorities, offering a targeted, evidence-based strategy to prevent these respiratory illnesses and their potentially fatal outcomes.