Cardiovascular System Exam

Correct Answer: A

Rationale: Automaticity is the correct answer because it refers to the inherent ability of cardiac cells to generate electrical impulses without the need for external stimulation. Contractility (Choice B) is the ability of the heart muscle to contract and generate force, not related to electrical impulse generation. Conductivity (Choice C) refers to the ability of cardiac cells to transmit electrical impulses from cell to cell, not the spontaneous generation of impulses. Refractoriness (Choice D) is the period during which the cardiac cells are recovering and not able to respond to a new stimulus, not the spontaneous generation of impulses.

Correct Answer: A

Rationale: Mitral regurgitation is the condition where the heart's mitral valve does not close properly, allowing blood to leak backward into the left atrium. This can result in symptoms like shortness of breath and fatigue. Choices B, C, and D are incorrect because aortic stenosis, tricuspid regurgitation, and pulmonary hypertension involve different heart valves or conditions, not the mitral valve specifically.

Correct Answer: A

Rationale: The correct answer is 'Bronchitis.' Bronchitis refers to the inflammation of the bronchial tubes, which can be acute or chronic, leading to symptoms like coughing and increased mucus production. Choice B, 'Asthma,' is a chronic condition characterized by inflammation and narrowing of the airways, often causing wheezing and shortness of breath. Choice C, 'Pneumonia,' is an infection that inflames air sacs in one or both lungs, leading to symptoms like fever, cough, and difficulty breathing. Choice D, 'Cystic fibrosis,' is a genetic disorder that affects the lungs and digestive system, causing mucus buildup and respiratory issues.

Correct Answer: A

Rationale: Excitability is the correct term that describes the ability of cardiac cells to respond to an impulse by contracting. Excitability refers to the cell's ability to respond to stimuli and generate an action potential. Choice B, Contractility, is incorrect as it refers to the ability of cardiac cells to contract after receiving a stimulus, not the response to the impulse itself. Choice C, Rhythmicity, is incorrect as it pertains to the heart's ability to contract rhythmically without external stimulation. Choice D, Conductivity, is incorrect as it refers to the ability of cardiac cells to transmit an impulse from cell to cell, not the direct response to the impulse by contracting.

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.