The ________ inhibit the apneustic centers and promote passive or active exhalation.
- A. DRG
- B. VRG
- C. pneumotaxic centers
- D. LRG
Correct Answer: C
Rationale: The correct answer is C: pneumotaxic centers. The pneumotaxic centers are located in the pons and regulate the rate and depth of breathing by inhibiting the apneustic centers in the medulla. This inhibition helps to promote passive or active exhalation.
A: DRG (dorsal respiratory group) is responsible for the initiation of inspiration.
B: VRG (ventral respiratory group) is involved in both inspiration and expiration.
D: LRG is not a recognized respiratory center in the brainstem.
In summary, the pneumotaxic centers play a crucial role in regulating breathing by inhibiting the apneustic centers, leading to exhalation.
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Which blood pressure (BP) finding by the nurse indicates that no changes in therapy are needed for a 78-yr-old patient with newly diagnosed hypertension?
- A. 98/56 mm Hg
- B. 118/76 mm Hg
- C. 128/92 mm Hg
- D. 142/78 mm Hg
Correct Answer: B
Rationale: The correct answer is B (118/76 mm Hg) because it falls within the recommended range for a 78-year-old patient with hypertension. The systolic BP should ideally be below 140 mm Hg and the diastolic BP below 90 mm Hg for this age group. Option A is too low for systolic BP, indicating hypotension. Option C has elevated diastolic BP, suggesting uncontrolled hypertension. Option D has high systolic BP, indicating a need for therapy adjustment. Thus, only option B aligns with the guidelines, making it the correct choice.
which of the following part of the ear separate middle ear from outer ear
- A. oval window
- B. round window
- C. Malleaus
- D. tympanic membrane
Correct Answer: D
Rationale: The correct answer is D: tympanic membrane because it separates the middle ear from the outer ear. The tympanic membrane, also known as the eardrum, vibrates in response to sound waves and transmits these vibrations to the middle ear. The oval window (A) is a membrane-covered opening in the inner ear that receives vibrations from the stapes bone. The round window (B) is a membrane-covered opening that equalizes pressure within the inner ear. The malleus (C) is a small bone in the middle ear that transmits sound vibrations from the eardrum to the incus. Therefore, the tympanic membrane is the correct answer as it physically separates the middle ear from the outer ear.
Foetal hemoglobin has a Sigmoid dissociation curve which is shifted to left relative to adult Hb because
- A. Foetal Hb has higher P50
- B. Foetal HB has lower P50 (18-20 mm Hg) than Adult Hb (26.6 mm.Hg)
- C. Foetal Hb readily accept Oxygen
- D. Foetal Hb easily remove Carbon dioxide
Correct Answer: B
Rationale: The correct answer is B because foetal Hb has a lower P50 (18-20 mm Hg) than adult Hb (26.6 mm Hg). A lower P50 indicates higher oxygen affinity, allowing foetal Hb to bind oxygen more readily at lower partial pressures. This shift to the left of the dissociation curve ensures efficient oxygen transfer from the maternal bloodstream to the foetus. Choices A, C, and D are incorrect because foetal Hb having a higher P50 (A), readily accepting oxygen (C), or easily removing carbon dioxide (D) would not explain the left shift in the dissociation curve.
Food and drink are prevented from entering the respiratory passageways during swallowing by means of the
- A. glottis.
- B. pharynx.
- C. epiglottis.
- D. larynx.
Correct Answer: C
Rationale: The correct answer is C: epiglottis. During swallowing, the epiglottis covers the opening of the larynx to prevent food and drink from entering the respiratory passageways. It acts as a lid that directs food and liquids to the esophagus instead of the trachea. The glottis (choice A) is the space between the vocal cords, the pharynx (choice B) is the passageway for food and air, and the larynx (choice D) contains the vocal cords. The epiglottis specifically functions to protect the airway during swallowing.
Which statement is false?
- A. Dorsal respiratory group in upper pons is responsible for inspiration
- B. Apneustic centre can inhibit the inspiratory centre
- C. Pneumotaxic centre is responsible for prolonged inspiratory gasp interrupted by transient expiratory efforts
- D. None of the above
Correct Answer: D
Rationale: The correct answer is D, None of the above, is false.
A: Dorsal respiratory group in the upper pons is indeed responsible for inspiration.
B: The apneustic centre can inhibit the inspiratory centre, so this statement is true.
C: The pneumotaxic centre is responsible for regulating the duration and depth of each breath, not for a prolonged inspiratory gasp interrupted by expiratory efforts.
Therefore, choice D is false as all the other statements are accurate.