Nokea
Oxygen moves from alveoli to the bloodstream
- A. because the concentration of oxygen is greater in alveoli than in the blood.
- B. mainly due to the activity of carbonic anhydrase in the red blood cells.
- C. by using the assistance of carbaminohemoglobin
- D. through active transport.
Correct Answer: A
Rationale: The correct answer is A because oxygen moves from alveoli to the bloodstream by simple diffusion. This is due to the concentration gradient of oxygen being higher in the alveoli (where oxygen is inhaled) compared to the blood vessels surrounding the alveoli. Oxygen molecules move from an area of high concentration (alveoli) to an area of low concentration (bloodstream) to reach equilibrium. Choices B, C, and D are incorrect because the movement of oxygen in this context is primarily driven by passive diffusion, not by the activity of carbonic anhydrase, carbaminohemoglobin, or active transport.
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Volume of air left after maximum forceful expiration in human lung is
- A. Total lung capacity
- B. Residual volume
- C. Vital capacity
- D. Tidal volume
Correct Answer: B
Rationale: The correct answer is B: Residual volume. After maximum forceful expiration, residual volume is the volume of air left in the lungs to prevent lung collapse. Total lung capacity (A) is the maximum amount of air the lungs can hold. Vital capacity (C) is the maximum amount of air that can be exhaled after a maximum inhalation. Tidal volume (D) is the volume of air moved in and out of the lungs during normal breathing, not after a forceful expiration.
Which teaching point is most important for the client with a peritonsillar abscess?
- A. Gargle with warm salt water.
- B. Take all antibiotics as directed.
- C. Let us know if you want liquid medications.
- D. Wash hands frequently.
Correct Answer: B
Rationale: The correct answer is B: Take all antibiotics as directed. This is the most important teaching point for a client with a peritonsillar abscess because antibiotics are crucial in treating the infection and preventing complications. Here's the rationale:
1. Antibiotics target the bacteria causing the abscess, helping to clear the infection.
2. Incomplete antibiotic course can lead to antibiotic resistance and recurrence of infection.
3. Not following antibiotic instructions can result in treatment failure and worsening of the abscess.
4. Gargling with warm salt water (choice A) may provide temporary relief but does not address the underlying infection. Liquid medications (choice C) and handwashing (choice D) are important but not as vital as completing the antibiotic course.
The most important chemical regulator of respiration is
- A. oxygen
- B. carbon dioxide
- C. bicarbonate ion
- D. sodium ion
Correct Answer: B
Rationale: The correct answer is B: carbon dioxide. Carbon dioxide is the most important chemical regulator of respiration as it directly affects the respiratory rate and depth. An increase in carbon dioxide levels in the blood triggers the body to increase respiration to expel the excess carbon dioxide. Conversely, a decrease in carbon dioxide levels signals the body to decrease respiration. Oxygen (choice A) is important for cellular respiration but does not directly regulate breathing. Bicarbonate ion (choice C) and sodium ion (choice D) do not play a direct role in regulating respiration.
Which of the following neurological controls of ventilation responds to changes in the pH and levels of oxygen and CO2 in the blood?
- A. Central chemoreceptors in the medulla
- B. Peripheral chemoreceptors in the aortic arch and carotid arteries
- C. Respiratory centers in the medulla oblongata and pons
- D. Central chemoreceptors in the spinal cord
Correct Answer: A
Rationale: The correct answer is A. Central chemoreceptors in the medulla are highly sensitive to changes in pH and CO2 levels, influencing respiratory rate and depth. B is incorrect because peripheral chemoreceptors respond mainly to O2 levels. C refers to general respiratory control centers, not specific chemoreceptor function. D is incorrect as the spinal cord lacks central chemoreceptors.
The ED nurse is assessing a patient complaining of dyspnea. The nurse auscultates the patient's chest and hears wheezing throughout the lung fields. What might this indicate?
- A. The patient has a narrowed airway.
- B. The patient has pneumonia.
- C. The patient needs physiotherapy.
- D. The patient has a hemothorax.
Correct Answer: A
Rationale: The correct answer is A: The patient has a narrowed airway. Wheezing throughout the lung fields indicates the presence of narrowed airways, often due to conditions like asthma or chronic obstructive pulmonary disease (COPD). Wheezing is caused by turbulent airflow through narrowed airways, leading to a high-pitched whistling sound during expiration. This is a characteristic finding in patients with obstructive airway diseases.
Summary of other choices:
B: The patient having pneumonia would typically present with symptoms like fever, cough, and consolidation on auscultation, not wheezing.
C: The patient needing physiotherapy may have respiratory muscle weakness or secretion clearance issues but would not typically present with wheezing throughout lung fields.
D: The presence of a hemothorax (blood in the pleural space) would manifest as decreased breath sounds and signs of respiratory distress but not wheezing.