A male client comes to the emergency department complaining of sudden onset of diarrhea, anorexia, malaise, cough, headache, and recurrent chills. Based on the client's history and physical findings, the physician suspects Legionnaires' disease. While awaiting diagnostic test results, the client is admitted to the facility and started on antibiotic therapy. What is the drug of choice for treating Legionnaires' disease?

Correct Answer: A

Rationale: The correct answer is A: erythromycin (Erythrocin). Legionnaires' disease is caused by the bacterium Legionella pneumophila, and erythromycin is the drug of choice for treating this infection. Erythromycin is a macrolide antibiotic that effectively targets Legionella bacteria by inhibiting their protein synthesis. It is bacteriostatic at low concentrations and bactericidal at higher concentrations. Rifampin (B) is not the preferred choice for Legionnaires' disease. Amantadine (C) is used for treating influenza A virus, not Legionella bacteria. Amphotericin B (D) is an antifungal agent and is not effective against Legionella pneumophila. Utilizing erythromycin as the treatment of choice ensures successful eradication of the Legionella bacteria and helps the client recover from the infection.

Correct Answer: C

Rationale: The correct answer is C: bronchioles. After air passes through the trachea, it enters the bronchi, which further divide into bronchioles. The bronchioles are the last structures where air passes before reaching the alveoli for gas exchange. The larynx is involved in sound production and the glottis is the opening between the vocal cords in the larynx. While the trachea is the initial passage for air into the respiratory system, the bronchioles are the final branching structures where air reaches the alveoli, making them the correct answer.

Correct Answer: D

Rationale: The correct answer is D because carbonic anhydrase catalyzes the conversion of carbon dioxide and water into bicarbonate ions and protons, not the formation of oxyhemoglobin. Step-by-step rationale: 1. Hemoglobin functions as a buffer by binding to hydrogen ions to help regulate pH levels in the blood. 2. Bicarbonate ions do tend to diffuse out of red blood cells into the plasma to maintain the balance of CO2 and pH. 3. The movement of molecules is indeed different in metabolically active tissues (where oxygen is released and CO2 is taken up) compared to the alveoli (where the opposite occurs). Therefore, choices A, B, and C are all correct statements, making D the false statement.

Correct Answer: D

Rationale: The correct order of structures in the respiratory passageways is D: pharynx, larynx, trachea, bronchi, bronchioles. This is the correct order because air enters the body through the pharynx, then passes through the larynx (voice box), followed by the trachea (windpipe), which branches into the bronchi, and then further divides into bronchioles. The other choices are incorrect because they do not follow the natural flow of air through the respiratory system. Choice A has the incorrect order starting with the pharynx, followed by the trachea, larynx, bronchi, and bronchioles. Choice B starts with the larynx, then pharynx, trachea, bronchioles, and bronchi, which is out of sequence. Choice C begins with the trachea, then pharynx, larynx, bronchi, and bronchioles, which is also incorrect

Correct Answer: B

Rationale: The correct answer is B: Pleurisy. Pleurisy is inflammation of the pleura, the lining around the lungs, causing severe chest pain. Emphysema (A) is a chronic lung condition causing shortness of breath, not chest pain. Asphyxia (C) is a condition of insufficient oxygen, not related to lung inflammation. Hypoxia (D) is low oxygen levels in tissues, not specific to lung covering inflammation. Pleurisy is the only choice directly related to inflammation of the lungs' covering, making it the correct answer.