Physical Exam Cardiovascular System

Correct Answer: A

Rationale: The correct answer is A, Excitability. Excitability is the ability of cardiac cells to respond to a stimulus by initiating a cardiac impulse. Choice B, Contractility, refers to the ability of cardiac muscle to shorten forcibly. Choice C, Rhythmicity, refers to the cardiac muscle's ability to contract rhythmically. Choice D, Conductivity, refers to the ability of the heart's cells to conduct electrical impulses.

Correct Answer: A

Rationale: The correct answer is Thoracentesis. Thoracentesis is a procedure specifically designed to remove excess fluid or air from the pleural space in the chest. This process helps to relieve pressure on the lungs and improve breathing. Bronchoscopy (Choice B) is a procedure used to visualize the airways and diagnose lung conditions, not to remove fluid from the pleural space. Chest X-ray (Choice C) is an imaging test that provides a picture of the structures inside the chest, including the lungs, heart, and bones. Arterial blood gas (ABG) test (Choice D) is a blood test that measures the levels of oxygen and carbon dioxide in the blood, providing information about how well the lungs are working, but it does not involve removing excess fluid or air from the pleural space.

Correct Answer: A

Rationale: The correct answer is an echocardiogram. This test utilizes sound waves to generate images of the heart, enabling doctors to evaluate both the function and structure of the heart. Choice B, MRI, uses magnetic fields and radio waves to produce detailed images of the body's organs and structures, not specifically focused on the heart. Choice C, CT scan, employs X-rays to create detailed cross-sectional images of the body, not primarily for the heart. Choice D, X-ray, uses electromagnetic radiation to produce images of internal structures, but it does not provide the detailed pictures of the heart's function that an echocardiogram does.

Correct Answer: A

Rationale: The correct answer is A: Chordae tendineae. Chordae tendineae are fibrous cords that connect the AV valves to the papillary muscles, preventing the valves from inverting during ventricular contraction. Papillary muscles (choice B) anchor the chordae tendineae to the ventricular wall but do not hold up the AV valves directly. Semilunar valves (choice C) are located between the ventricles and the major arteries and are not involved in holding up the AV valves. The aortic valve (choice D) is one of the semilunar valves and is not responsible for holding up the AV valves.

Correct Answer: B

Rationale: The correct answer is B: Approximately 70 mL of blood per beat. The stroke volume of the heart is typically around 70 mL, indicating the volume of blood ejected from the left ventricle with each contraction. Choices A, C, and D are incorrect as they do not represent the standard approximate stroke volume of the heart, which is around 70 mL per beat.