The nurse is caring for a client diagnosed with pneumonia resulting from Staphylococcus aureus. Which classification of medication should the nurse anticipate the healthcare provider will order to eradicate the infection?

Correct Answer: B

Rationale: Cephalosporin (B) (e.g., cefazolin) targets Staphylococcus aureus pneumonia, per IDSA guidelines its beta-lactam kills gram-positive cocci. Corticosteroids (A) reduce inflammation, not infection. Antitussives (C) suppress cough, delaying clearance. Bronchodilators (D) ease breathing, not eradication. S. aureus's virulence (e.g., necrotizing) requires antibiotics like B, aligning with the document's implied answer, distinguishing it from A's adjunct role or C's symptom focus.

Correct Answer: A

Rationale: In birds (Aves), gas exchange occurs in the lungs, not air sacs. Their unique system features rigid lungs with parabronchi, where oxygen and carbon dioxide diffuse into blood continuously, unlike human tidal breathing. Air sacs act as bellows, moving air unidirectionally through the lungs, but lack capillaries for exchange they store and pump air. 'Air sacs and lungs' overstates sacs' role; 'none' is wrong lungs are key. This efficient design supports high metabolism for flight, a distinct adaptation in avian respiration, critical for understanding comparative physiology and bird-specific respiratory conditions.

Correct Answer: B

Rationale: The anterior interventricular sulcus, a groove on the heart's front surface, marks the boundary between the right and left ventricles, housing the anterior interventricular artery. The coronary sulcus encircles the heart, separating atria from ventricles. The posterior interventricular sulcus, on the back, also divides ventricles but is less prominent anteriorly. The coronary sinus is a vein, not a groove. This sulcus's visibility and vascular role make it a key landmark, guiding surgical and imaging approaches, essential in cardiac anatomy for locating ventricular divisions.

Correct Answer: C

Rationale: Gap junctions electrically connect cardiac muscle fibers, allowing rapid ion flow between cells via connexin channels, synchronizing contractions across the myocardium for a unified heartbeat. Desmosomes anchor fibers mechanically, not electrically. Tight junctions seal cells, rare in heart tissue. Interneurons are neural, not muscular. These gap junctions, within intercalated discs, enable the heart's autorhythmic, coordinated action, a key feature distinguishing cardiac from skeletal muscle, essential in physiology and arrhythmias where connectivity falters, disrupting rhythm.

Correct Answer: C

Rationale: Increased plasma potassium (hyperkalemia) decreases heart rate by depolarizing cardiac cells, slowing pacemaker activity and conduction severe cases stop the heart. Norepinephrine (sympathetic) and thyroid hormone increase rate by boosting metabolism and SA node firing. Increased calcium enhances contractility, not slowing rate in excess, it speeds it. Potassium's membrane effect, shifting resting potential, disrupts rhythm, a clinical concern in renal failure or drug effects, contrasting with stimulatory factors, key in ECG changes and arrhythmia management.