Cardiovascular System Exam

Correct Answer: A

Rationale: The correct answer is A: Right atrium. The right atrium is the heart chamber that receives deoxygenated blood returning from the body via the superior and inferior vena cava. The blood enters the right atrium from the vena cava and then passes through the tricuspid valve into the right ventricle. Choices B, C, and D are incorrect because the left atrium receives oxygenated blood from the lungs, the right ventricle pumps blood to the lungs for oxygenation, and the left ventricle pumps oxygenated blood to the body.

Correct Answer: A

Rationale: Paroxysmal nocturnal dyspnea is the correct answer. It is characterized by sudden episodes of severe shortness of breath during sleep, often waking the individual. Choice B, Sleep apnea, involves pauses in breathing during sleep but does not usually present with acute shortness of breath. Choice C, Orthopnea, refers to shortness of breath that occurs when lying flat and is relieved by sitting up. Choice D, Dyspnea, is a general term for difficult or labored breathing and does not specifically describe acute episodes at night.

Correct Answer: A

Rationale: The correct answer is A, Myocarditis. Myocarditis is an inflammation of the heart muscle, typically caused by a viral infection. It can impair the heart's ability to pump blood efficiently, potentially leading to other complications. Endocarditis (choice B) is an inflammation of the inner lining of the heart chambers and valves. Pericarditis (choice C) is inflammation of the pericardium, the outer lining of the heart. Cardiomyopathy (choice D) is a disease of the heart muscle that affects the heart's ability to pump blood.

Correct Answer: A

Rationale: The correct answer is A: Right atrium. The right atrium is the heart chamber that receives deoxygenated blood returning from the body via the superior and inferior vena cava. The blood enters the right atrium from the vena cava and then passes through the tricuspid valve into the right ventricle. Choices B, C, and D are incorrect because the left atrium receives oxygenated blood from the lungs, the right ventricle pumps blood to the lungs for oxygenation, and the left ventricle pumps oxygenated blood to the body.

Correct Answer: A

Rationale: Atherosclerosis is the correct answer. It is the buildup of plaque in the arteries, leading to the narrowing of blood vessels, reduced blood flow, and an increased risk of heart attacks, strokes, and other cardiovascular diseases. Arteriosclerosis (choice B) refers to the hardening and thickening of arterial walls, while hypertension (choice C) is high blood pressure, and diabetes (choice D) is a metabolic disorder characterized by high blood sugar levels. Therefore, choices B, C, and D are incorrect in the context of the question.