Which of the following is not directly connected to the nasopharynx?

Correct Answer: C

Rationale: The nasopharynx, part of the upper throat behind the nasal cavity, connects directly to several structures. The middle ear links via the Eustachian tube, regulating pressure and draining mucus. The oropharynx lies below, sharing a continuous passage for air and food. The nasal cavity opens into it anteriorly, forming the primary airway. However, the lacrimal glands, located near the eyes, connect to the nasal cavity via the nasolacrimal duct, not the nasopharynx directly tears drain into the nose, bypassing the nasopharynx. This indirect link makes lacrimal glands the exception. Understanding these anatomical relationships is key in respiratory health, as infections can spread via these connections, but the lacrimal glands' drainage path distinguishes them, aligning with their role in tear production rather than respiratory function.

Correct Answer: B

Rationale: The nurse's response (B) reflects Pneumocystis jiroveci's transmission ubiquitous in the environment, it can be carried asymptomatically by others (e.g., visitors) and inhaled by immunocompromised hosts (e.g., HIV, CD4 <200). Choice A is false; it's not waterborne (unlike Legionella). Choice C is incorrect; transmission is known airborne via respiratory droplets or reactivation of latent infection. Choice D is wrong; it's not foodborne (e.g., Toxoplasma). The document's answer (B) aligns with pathophysiology P. jiroveci's opportunistic nature means masks may not fully protect indoors if others introduce it, distinguishing it from A's route or C's uncertainty.

Correct Answer: D

Rationale: A nonrebreather mask (D) delivers 100% oxygen (FiOâ‚‚ 0.9-1.0) for severe pneumonia hypoxemia (PaOâ‚‚ <60 mmHg), per nursing texts. Simple mask (A) maxes at 60%. Venturi (B) adjusts FiOâ‚‚ (24-50%), not 100%. Nasal cannula (C) reaches 40%. The document's answer (D) fits nonrebreather's reservoir ensures high FiOâ‚‚, critical for ARDS-like pneumonia, distinguishing it from A's lower capacity or C's inadequacy.

Correct Answer: C

Rationale: Carbon dioxide (CO2) is released during respiration, a byproduct of cellular metabolism where glucose and oxygen produce energy, water, and CO2 in mitochondria. This CO2 diffuses from tissues into the blood, is transported to the lungs, and exhaled via alveoli. Oxygen is consumed, not released it enters the blood. Hydrogen isn't a respiratory gas; it's part of water or metabolic intermediates. 'None' is incorrect CO2 expulsion is respiration's hallmark. This process balances blood pH and oxygen levels, critical for homeostasis, distinguishing respiration from photosynthesis, where CO2 is absorbed, a fundamental principle in physiology and gas exchange studies.

Correct Answer: D

Rationale: Normal breathing is controlled by the ventral and dorsal respiratory groups in the medulla and pons. The dorsal group initiates inspiration, stimulating the diaphragm via the phrenic nerve, while the ventral group adjusts forceful breathing, and the pons refines rhythm together maintaining automatic respiration based on CO2 levels. Lungs execute breathing but don't control it they respond to neural signals. This brain stem coordination ensures steady, involuntary breathing, adapting to metabolic needs, a critical autonomic process distinct from voluntary control, foundational in respiratory physiology and clinical monitoring of breathing disorders.