ATI LPN
Questions on the Respiratory System Questions
Question 1 of 5
The windpipe is also called the ________.
Correct Answer: C
Rationale: The windpipe is the trachea, a tube of C-shaped cartilage rings extending from the larynx to the bronchi, conducting air to the lungs while filtering it with cilia and mucus. The larynx, above, houses vocal cords. Lungs are the exchange organs, not a tube. The esophagus transports food, not air. 'Trachea' is the precise term, reflecting its role as the airway's main conduit, essential for breathing, a key anatomical distinction in respiratory structure and function, critical for procedures like tracheostomy.
Question 2 of 5
Which network of specialized cardiac muscle fibers provide a path for each cycle of cardiac excitation to progress through the heart?
Correct Answer: D
Rationale: The cardiac conduction system sinoatrial (SA) node, atrioventricular (AV) node, bundle of His, and Purkinje fibers provides the path for electrical excitation, pacing the heartbeat from SA node initiation through ventricular contraction. The systemic circuit is blood flow, not conduction. Intercalated discs connect fibers, not a network. The cardiovascular center in the medulla regulates rate, not the path. This system's specialized fibers ensure rapid, orderly spread, critical for synchronized pumping, a cornerstone of cardiac physiology and target in conduction disorders like heart block.
Question 3 of 5
Which wave in an electrocardiogram represents repolarization of the ventricles?
Correct Answer: B
Rationale: The T wave on an ECG represents ventricular repolarization, when potassium exits cells, relaxing the myocardium after systole key to resetting for the next beat. The R wave, part of the QRS complex, shows ventricular depolarization and contraction. The S wave completes QRS, not repolarization. The P wave is atrial depolarization. The T wave's shape and timing reflect recovery, critical in diagnostics e.g., inverted T waves signal ischemia making it a cornerstone of ECG interpretation and cardiac health assessment.
Question 4 of 5
The saclike structure around the heart is the:
Correct Answer: D
Rationale: The pericardium, a saclike structure, encases the heart fibrous pericardium anchors it, serous layers (parietal, visceral/epicardium) reduce friction. The epicardium is the heart's outer layer within this sac, myocardium the muscle, endocardium the inner lining. This sac's dual role protection, lubrication is vital, key in pericardial diseases like tamponade, a fundamental cardiac enclosure in anatomy.
Question 5 of 5
Of the four parts of respiration, the part when oxygen and carbon dioxide are exchanged in the body's tissue cells, is:
Correct Answer: D
Rationale: Internal respiration (D) is the O₂ and CO₂ exchange between blood and tissue cells, per the key. Pulmonary ventilation (A) moves air into lungs (e.g., 6-8 L/min at rest). External respiration (B) occurs in alveoli. Transport of respiratory gases (C) is blood-mediated (e.g., 98% O₂ on Hb). At tissues, O₂ unloads (PvO₂ ≈40 mmHg) to cells, and CO₂ (PvCO₂ ≈46 mmHg) enters blood, per Bohr effect (pH shift). This cellular gas swap vital for metabolism (e.g., 250 mL/min O₂ use) defines D, contrasting with A's airflow, B's lung focus, or C's transit role, making internal respiration the tissue-specific process.