Cardiovascular System Exam

Correct Answer: A

Rationale: Bradycardia is the correct answer. It is a condition characterized by a slow heart rate, which reduces the amount of blood pumped to the body. This can lead to symptoms like fatigue and dizziness. Choice B, Tachycardia, is the opposite condition where the heart beats too fast. Choices C and D, Atrial fibrillation and Ventricular fibrillation, refer to irregular and potentially life-threatening rapid heart rhythms involving the atria and ventricles respectively, not a slow heart rate.

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: Pleural effusion is the correct answer as it refers to the accumulation of excess fluid between the layers of the pleura surrounding the lungs and chest cavity. This condition can be caused by various factors such as infections, heart failure, or cancer. Pulmonary edema (choice B) involves fluid accumulation in the lungs' air sacs and is not specific to the pleura. Atelectasis (choice C) is the collapse or closure of a lung leading to airless lung tissue and is not related to fluid buildup. Sarcoidosis (choice D) is a condition characterized by the growth of tiny collections of inflammatory cells in different parts of the body, not specifically involving fluid accumulation in the pleural space.

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: The correct answer is A, Arrhythmia. Arrhythmia refers to an irregular heartbeat caused by the malfunction of the heart's electrical system. Bradycardia (choice B) is a condition characterized by a slow heart rate, while Tachycardia (choice C) is a condition characterized by a fast heart rate. Ventricular fibrillation (choice D) is a life-threatening arrhythmia where the heart's lower chambers quiver erratically.