Nokea
Which neurotransmitter released by the parasympathetic nervous system can decrease heart rate?
- A. Acetylcholine
- B. Norepinephrine
- C. Dopamine
- D. Serotonin
Correct Answer: A
Rationale: The correct answer is A: Acetylcholine. Acetylcholine is released by the parasympathetic nervous system and acts on the heart to decrease heart rate. It binds to muscarinic receptors in the heart, leading to a decrease in heart rate through inhibition of the SA node. Norepinephrine (B) is released by the sympathetic nervous system and increases heart rate. Dopamine (C) and Serotonin (D) are not directly involved in regulating heart rate through the parasympathetic pathway.
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Which term describes an abnormal heartbeat that can be either too fast or too slow?
- A. Arrhythmia
- B. Bradycardia
- C. Tachycardia
- D. Conductivity
Correct Answer: A
Rationale: The correct answer is A: Arrhythmia. An arrhythmia refers to an abnormal heartbeat rhythm, which can be too fast (tachycardia) or too slow (bradycardia). Arrhythmia encompasses both of these irregularities. Choice B, bradycardia, specifically refers to a slow heartbeat, while choice C, tachycardia, specifically refers to a fast heartbeat. Choice D, conductivity, is not directly related to the speed or rhythm of the heartbeat, making it an incorrect choice.
How might the blood pressure be affected in a client whose body mass index (BMI) is 31 (obese)?
- A. increased
- B. decreased
- C. no change
- D. a change either way
Correct Answer: A
Rationale: Obesity is strongly associated with increased blood pressure due to factors like insulin resistance and increased vascular resistance.
What is a chronic lung disease that includes chronic bronchitis and emphysema?
- A. Chronic Obstructive Pulmonary Disease (COPD)
- B. Pneumonia
- C. Asthma
- D. Tuberculosis
Correct Answer: A
Rationale: The correct answer is A: Chronic Obstructive Pulmonary Disease (COPD). COPD is a chronic lung disease characterized by chronic bronchitis and emphysema. Chronic bronchitis involves inflammation of the bronchial tubes, leading to excessive mucus production. Emphysema is the destruction of lung tissue, resulting in difficulty breathing. Pneumonia (B) is an acute infection of the lungs. Asthma (C) is a chronic condition characterized by airway inflammation and constriction. Tuberculosis (D) is an infectious disease caused by Mycobacterium tuberculosis affecting the lungs. Therefore, the correct answer is A as it specifically encompasses chronic bronchitis and emphysema, distinguishing it from the other options.
A patient uses a mixed β-adrenergic blocking drug for treatment of migraine headaches. What effect might this drug have on BP and why?
- A. Decreased BP due to reduced cardiac output
- B. Increased BP due to unopposed α-adrenergic activity
- C. No effect on BP
- D. Decreased BP due to vasodilation
Correct Answer: A
Rationale: β-blockers reduce heart rate and contractility, lowering BP.
Which of the following symptoms is the first sign of aortic regurgitation?
- A. Water-hammer pulse
- B. Tachycardia
- C. Flushed skin
- D. Heart murmur
Correct Answer: A
Rationale: A water-hammer pulse is an early sign of aortic regurgitation due to backflow of blood into the left ventricle.