ATI LPN
Questions for Respiratory System Questions
Question 1 of 5
The nurse is caring for a client with pneumonia-related atelectasis. Which action would be most appropriate for the nurse to implement to improve oxygen saturation?
Correct Answer: D
Rationale: Instructing incentive spirometer use (D) best improves Oâ‚‚ saturation in pneumonia-related atelectasis deep breathing (e.g., 10 breaths/hour) re-expands alveoli, per ATS. High-flow Oâ‚‚ (A) treats hypoxemia, not atelectasis. Postural drainage (B) or percussion (C) clears mucus, less effective for collapse. The document's answer (D) fits spirometry (e.g., 1500 mL) reverses shunting (SpOâ‚‚ <92%), distinguishing it from A's supportive role.
Question 2 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 3 of 5
What type of tissue comprises the valves of the heart?
Correct Answer: A
Rationale: Heart valves are made of dense connective tissue, primarily collagen, providing strength and flexibility to withstand pressure changes, with a core of fibrous tissue layered by endothelium. Areolar connective tissue is loose, not robust enough. Hyaline cartilage is rigid, found in the trachea, not valves. Cardiac muscle forms the heart wall, not valves. This dense tissue, avascular and resilient, ensures durability cusps flex without stretching key in valve function, relevant in pathology like calcification where flexibility diminishes, impacting flow.
Question 4 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 5 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.