Nokea
Which of the following is a central vasodilator and peripheral vasoconstrictor?
- A. Sympathetic nervous system
- B. Parasympathetic nervous system
- C. Norepinephrine
- D. Acetylcholine
Correct Answer: A
Rationale: The correct answer is A: Sympathetic nervous system. The sympathetic nervous system releases norepinephrine, which acts as a central vasodilator by dilating blood vessels in the heart and skeletal muscles. It also acts as a peripheral vasoconstrictor by constricting blood vessels in other areas to redirect blood flow to vital organs during fight-or-flight responses.
B: Parasympathetic nervous system is incorrect as it primarily promotes rest and digestion, not vasodilation or vasoconstriction.
C: Norepinephrine is incorrect as it acts as a peripheral vasoconstrictor, not a central vasodilator.
D: Acetylcholine is incorrect as it primarily functions in the parasympathetic nervous system and is not associated with central vasodilation or peripheral vasoconstriction.
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In developing a teaching plan for Mr. Jones on hydrochlorothiazide, it would be important to include
- A. avoiding consumption of alcoholic beverages
- B. restricting potassium intake
- C. increasing fluid intake
- D. restricting physical activity
Correct Answer: A
Rationale: Alcohol can exacerbate diuretic effects.
What test measures the electrical activity of the heart over a period of time, typically 24 to 48 hours?
- A. Holter monitor
- B. Echocardiogram
- C. Stress test
- D. Arterial blood gas (ABG)
Correct Answer: A
Rationale: The correct answer is A: Holter monitor. A Holter monitor is a device that measures the electrical activity of the heart over an extended period, usually 24 to 48 hours. It is used to detect abnormal heart rhythms and assess how the heart responds to daily activities.
Explanation:
1. The Holter monitor records the heart's electrical activity continuously, providing a detailed analysis of any irregularities.
2. Unlike an echocardiogram, which uses sound waves to create images of the heart, the Holter monitor focuses on monitoring electrical signals.
3. A stress test evaluates the heart's performance under physical stress, not over an extended period like the Holter monitor.
4. Arterial blood gas (ABG) measures oxygen and carbon dioxide levels in the blood, not the heart's electrical activity.
In summary, the Holter monitor is the correct choice as it specifically measures the heart's electrical activity over an extended timeframe, distinguishing it from the other options.
From where do these originate, behind the cusps of the aortic valve, in an area known as Valsalva's sinus?
- A. Pulmonary valve
- B. Aortic valve
- C. Tricuspid valve
- D. Mitral valve
Correct Answer: B
Rationale: Rationale: The correct answer is B - Aortic valve. This is because Valsalva's sinus is located behind the cusps of the aortic valve. The sinuses of Valsalva are pouch-like dilations found at the root of the aorta, just above the aortic valve. These sinuses are important in preventing backflow of blood into the heart during diastole. The other choices, A, C, and D, are incorrect because they do not originate from Valsalva's sinus. The pulmonary valve is located in the pulmonary artery, the tricuspid valve is between the right atrium and right ventricle, and the mitral valve is between the left atrium and left ventricle.
Which condition is characterized by an inability to effectively pump blood, leading to fluid buildup and swelling in the body?
- A. Heart failure
- B. Cardiomyopathy
- C. Angina
- D. Myocarditis
Correct Answer: A
Rationale: Step 1: Heart failure is characterized by the heart's inability to effectively pump blood, leading to fluid buildup and swelling.
Step 2: Cardiomyopathy is a disease of the heart muscle, which may contribute to heart failure but is not the direct cause of fluid buildup.
Step 3: Angina is chest pain due to reduced blood flow to the heart, not directly related to fluid buildup.
Step 4: Myocarditis is inflammation of the heart muscle, which can lead to heart failure but is not the primary cause of fluid accumulation.
Summary: Heart failure is the correct answer as it directly relates to the inability of the heart to pump blood effectively, leading to fluid accumulation. Cardiomyopathy, angina, and myocarditis are related to heart health but do not directly cause fluid buildup in the body.
Which condition involves the heart muscle becoming abnormally thickened, reducing its ability to pump blood?
- A. Hypertrophic cardiomyopathy
- B. Dilated cardiomyopathy
- C. Restrictive cardiomyopathy
- D. Ischemic cardiomyopathy
Correct Answer: A
Rationale: Step-by-step rationale:
1. Hypertrophic cardiomyopathy (A) is the correct answer.
2. In this condition, the heart muscle thickens, leading to decreased blood pumping ability.
3. This thickening can obstruct blood flow and increase the risk of abnormal heart rhythms.
4. Dilated cardiomyopathy (B) involves the heart enlarging and weakening, not thickening.
5. Restrictive cardiomyopathy (C) involves stiffening of the heart muscle, not thickening.
6. Ischemic cardiomyopathy (D) results from reduced blood flow to the heart, not thickening.