Nokea
During inspiration, air passes into lungs due to
- A. Increase in volume of thoracic cavity and fall in lung pressure
- B. Fall in pressure inside the lungs
- C. Increased volume of thoracic cavity
- D. Muscular expansion of lungs
Correct Answer: A
Rationale: Correct Answer: A - Increase in volume of thoracic cavity and fall in lung pressure
Rationale:
1. During inspiration, the diaphragm contracts and moves downward, increasing the volume of the thoracic cavity.
2. The external intercostal muscles also contract, lifting the ribcage and further expanding the thoracic cavity.
3. As thoracic cavity volume increases, lung pressure decreases, creating a pressure gradient that allows air to flow into the lungs.
Summary:
B: Fall in pressure inside the lungs - This is a consequence of the increase in thoracic cavity volume, not the cause of air entering the lungs.
C: Increased volume of thoracic cavity - This is correct but does not explain how air enters the lungs.
D: Muscular expansion of lungs - Lungs do not expand on their own; it is the thoracic cavity that expands to create the pressure gradient for air entry.
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What is the proper sequence in the flow of air in humans?
- A. nasal cavities, larynx, pharynx, bronchi, trachea
- B. nasal cavities, pharynx, bronchi, larynx, trachea
- C. nasal cavities, pharynx, larynx, trachea, bronchi
- D. nasal cavities, larynx, pharynx, trachea, bronchi
Correct Answer: C
Rationale: The correct sequence is C: nasal cavities, pharynx, larynx, trachea, bronchi. Air enters through the nasal cavities, passes through the pharynx, then the larynx where the vocal cords are located, then enters the trachea, and finally branches into the bronchi leading to the lungs. This sequence follows the anatomical pathway of the respiratory system, ensuring proper filtration, warming, and humidification of the air. Choices A, B, and D have incorrect sequences that do not follow the anatomical order of the respiratory pathway, leading to an inaccurate flow of air in humans.
A patient with pneumonia has a nursing diagnosis of ineffective airway clearance related to pain, fatigue, and thick secretions. What is an expected outcome for this patient?
- A. SpO is 90%
- B. Lungs clear to auscultation
- C. Patient tolerates walking in hallway
- D. Patient takes three or four shallow breaths before coughing to minimize pain
Correct Answer: D
Rationale: The expected outcome for a patient with ineffective airway clearance would be for the patient to take three or four shallow breaths before coughing to minimize pain, which indicates effective clearing of airway secretions. The other options do not directly relate to the nursing diagnosis provided.
In an older client, the alveolar walls become thinner and contain fewer capillaries. What does this condition lead to?
- A. Loss of elasticity in the lungs
- B. Decreased gas exchange
- C. Increased stiffness in lungs
- D. Decreased numbers of alveoli
Correct Answer: B
Rationale: The correct answer is B (Decreased gas exchange). Thinning alveolar walls and reduced capillary density directly impair the diffusion of gases across the alveolar-capillary membrane, leading to decreased gas exchange. While A (loss of elasticity) might occur with aging, it is not the primary consequence here. C (increased stiffness) is incorrect because stiffness typically results from fibrosis or other conditions, not thinning walls. D (decreased numbers of alveoli) could happen but is unrelated to the specific scenario described.
The impulse for voluntary muscles for forced breathing starts in
- A. Medulla ( pons )
- B. Vagus nerve
- C. Cerebral hemispheres
- D. Spinal cord
Correct Answer: A
Rationale: The correct answer is A: Medulla (pons). The medulla, located in the brainstem, controls involuntary functions like breathing. Specifically, the medulla contains the respiratory center, which regulates breathing rhythm and depth. During forced breathing, the medulla sends impulses to the voluntary muscles involved in breathing, such as the diaphragm and intercostal muscles. The pons, which is closely connected to the medulla, assists in regulating breathing patterns. The vagus nerve (B) is responsible for parasympathetic functions, not voluntary breathing. The cerebral hemispheres (C) are primarily involved in higher brain functions, not breathing regulation. The spinal cord (D) plays a role in transmitting signals between the brain and muscles but does not initiate voluntary breathing impulses.
Internal intercostal muscles are used in ...
- A. inspiration
- B. expiration
- C. both of them
- D. pause
Correct Answer: B
Rationale: The correct answer is B: expiration. The internal intercostal muscles are used during expiration to decrease the size of the thoracic cavity, increasing the pressure in the lungs, causing air to be pushed out. During inspiration, the external intercostal muscles are used to expand the thoracic cavity. Choice A is incorrect as it refers to inspiration. Choice C is incorrect because internal intercostal muscles are not involved in both inspiration and expiration simultaneously. Choice D is incorrect as there is no specific muscle action associated with a "pause" in breathing.