The nurse is conducting a teaching session for new parents on the causes of viral pneumonia. Which cause should the nurse include in the teaching? (Select all that apply.)

Correct Answer: A

Rationale: Adenovirus (A), Cytomegalovirus (CMV), and Influenza virus are viral pneumonia causes, but A is emphasized in teaching per the document. Norovirus (B) causes gastroenteritis, not pneumonia. CMV (C) affects immunocompromised (e.g., neonates), Influenza (D) is common in all ages, and Adenovirus spreads in kids via droplets. The rationale focuses on A its respiratory tropism (e.g., ARDS risk) makes it key for parents, distinguishing it from B's GI focus while noting C and D's relevance.

Correct Answer: C

Rationale: The human lungs contain about 500 million alveoli, a figure derived from anatomical studies estimating 480-600 million across both lungs. These sacs provide a massive surface area (around 100 m²) for gas exchange, vital for oxygenating blood efficiently. One billion or 1.5 billion overestimate this such numbers exceed histological counts. Eight hundred million is closer but still high. This 500 million estimate balances lung capacity with microscopic reality, supporting respiration's demands. Understanding this scale is key in physiology and pathology, like in COPD, where alveolar loss reduces exchange capacity, affecting oxygen delivery.

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.

Correct Answer: C

Rationale: The tricuspid valve allows blood to pass from the right atrium to the right ventricle, opening during diastole and closing during systole to prevent backflow its three cusps ensure one-way flow. The bicuspid (mitral) valve serves the left side. The interventricular septum separates ventricles, not a passage. The mitral valve is left-sided, not right. Named for its three leaflets, the tricuspid's role is pivotal in right heart circulation, a fundamental valve in cardiac flow, critical in conditions like tricuspid regurgitation affecting pulmonary return.

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.