Cardiovascular System Exam Questions And Answers

Correct Answer: A

Rationale: The correct answer is A, Frank-Starling's Law. This law explains that within physiologic limits, the greater the stretch of myocardial fibers, the more forceful the ventricular contraction, leading to an increased stroke volume. Choice B, Automaticity, refers to the ability of cardiac cells to spontaneously generate electrical impulses. Choice C, Contractility, represents the intrinsic ability of the heart muscle to contract. Choice D, Excitability, refers to the ability of cardiac cells to respond to electrical stimuli.

Correct Answer: A

Rationale: Goodpasture syndrome is the correct answer. It is an autoimmune disease characterized by the immune system attacking the lungs and kidneys, leading to bleeding in the lungs and kidney failure. Sarcoidosis primarily affects the lungs and lymph nodes, not the kidneys. Wegener's granulomatosis affects the lungs, sinuses, and kidneys, but it is characterized by inflammation of blood vessels. Interstitial lung disease involves scarring of the lung tissue, not direct immune system attacks on the lungs and kidneys.

Correct Answer: D

Rationale: The correct answer is D, Epinephrine. Epinephrine acts as a central vasoconstrictor and peripheral vasodilator. It increases heart rate and blood flow to muscles, helping to prepare the body for a 'fight or flight' response. Parasympathetic nervous system (choice A) does not cause vasoconstriction but rather vasodilation. The sympathetic nervous system (choice B) is primarily responsible for the fight or flight response, causing vasoconstriction. Dopamine (choice C) primarily acts as a neurotransmitter and hormone, not directly causing central vasoconstriction and peripheral vasodilation.

Correct Answer: A

Rationale: The correct answer is A, Calcium channel blocker. Calcium channel blockers work by relaxing the blood vessels, making it easier for the heart to pump blood and reducing blood pressure. Choice B, ACE inhibitor, reduces blood pressure by blocking the production of angiotensin II, a substance that narrows blood vessels. Choice C, Beta-blocker, reduces heart rate and the heart's workload, not directly relaxing blood vessels. Choice D, Diuretic, reduces blood pressure by increasing urine output, reducing the volume of fluid in the blood vessels, rather than directly relaxing them.

Correct Answer: A

Rationale: Alpha agonists are used for hemostasis to help control bleeding by constricting blood vessels, leading to decreased blood flow to the area. Choices B, C, and D are incorrect as alpha agonists do not typically dilate arteries, dilate veins, or decrease afterload.