ATI LPN
Questions for Respiratory System Questions
Question 1 of 5
In Earthworms, the process of respiration is through ________.
Correct Answer: A
Rationale: Earthworms respire through their skin, a moist, permeable surface allowing oxygen to diffuse into blood vessels beneath and carbon dioxide to exit no lungs or specialized organs exist. The head isn't a respiratory focus; respiration spans the body. Lungs are absent earthworms lack a respiratory tract. Anterior pores misrepresent skin diffusion, which occurs across all segments. This cutaneous respiration requires dampness, as oxygen dissolves in mucus, a simple yet effective adaptation for soil-dwellers, contrasting with complex lung systems, a key comparative physiology insight.
Question 2 of 5
Which of the following correctly lists the sequence of structures that a cardiac action potential follows in order to excite normal contraction of the heart?
Correct Answer: D
Rationale: The cardiac action potential follows: SA node (pacemaker, initiates), AV node (delays signal), bundle of His (transmits to ventricles), Purkinje fibers (spreads to ventricular myocardium), driving normal contraction. Other sequences disrupt this flow e.g., starting with Purkinje or misordering AV node delays atrial-ventricular timing. This precise path, from SA node atop the right atrium to Purkinje's ventricular reach, ensures atria contract before ventricles, optimizing filling and ejection, a fundamental rhythm in cardiac physiology, disrupted in arrhythmias like bundle branch block.
Question 3 of 5
Which of the following selections lists conditions that would lead to increased stroke volume?
Correct Answer: C
Rationale: Increased stroke volume (SV) blood ejected per beat results from increased preload (more venous return stretches ventricles, per Frank-Starling), decreased afterload (lower arterial resistance eases ejection), and increased contractility (stronger myosin-actin interaction, often catecholamine-driven). Increased afterload resists ejection, reducing SV. Decreased preload or contractility lowers filling or force, cutting SV. This trio optimizes SV by enhancing filling, easing outflow, and boosting power, key in exercise or heart failure management where these factors shift, a core concept in cardiac output dynamics.
Question 4 of 5
Which of the following is another name for the visceral layer of the pericardium?
Correct Answer: B
Rationale: The epicardium is another name for the visceral pericardium, the serous layer adhering to the heart's surface, distinct from the parietal pericardium and fibrous outer sac. Endocardium lines chambers, myocardium is muscle, fibrous pericardium is external. This synonym reflects its pericardial role, key in friction reduction, critical in epicardial pathology like inflammation, a precise layer nomenclature.
Question 5 of 5
The organs of the respiratory system include all the following EXCEPT:
Correct Answer: D
Rationale: Body tissues (D) are not respiratory system organs, per the key they're served by it. The nose (A) filters/warms air (e.g., 10000 L/day). The trachea (B) conducts air (cartilage-supported). Lungs (C) exchange gases (300 million alveoli). The respiratory system nose, pharynx, larynx, trachea, bronchi, lungs delivers Oâ‚‚ and removes COâ‚‚, per anatomy texts. Tissues (e.g., muscles, liver) use Oâ‚‚ but aren't part of this system; they're the endpoint of internal respiration. This excludes D, unlike A's entry point, B's conduit, or C's gas exchange role tissues rely on, but don't constitute, the respiratory apparatus.