Physical Exam Cardiovascular System

Correct Answer: A

Rationale: Oxygen therapy is the correct answer because it specifically refers to a treatment that delivers high concentrations of oxygen to the lungs. This therapy is used for patients who require additional oxygen due to conditions affecting their breathing. Ventilator therapy (B), mechanical ventilation (C), and CPAP therapy (D) involve different mechanisms and purposes than delivering high concentrations of oxygen to the lungs.

Correct Answer: A

Rationale: Acetylcholine is the correct answer. It is a neurotransmitter released by the parasympathetic nervous system that can decrease heart rate. Norepinephrine, dopamine, and serotonin are neurotransmitters that usually have different effects on the body and are not specifically associated with decreasing heart rate. Norepinephrine, for example, is often related to the fight-or-flight response and can increase heart rate.

Correct Answer: A

Rationale: Asthma is the correct answer. It is a chronic inflammatory disease of the airways characterized by episodes of wheezing, breathlessness, chest tightness, and coughing. These symptoms are often triggered by allergens or exercise. Bronchitis is an inflammation of the bronchial tubes, but it is not typically chronic or involve the same triggers as asthma. Pneumonia is an infection of the lungs, and emphysema is a type of chronic obstructive pulmonary disease (COPD) often caused by smoking.

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 A: Arrhythmia. Arrhythmia is a broad term that refers to any irregularity in the heart's rhythm, which can manifest as a heartbeat that is too fast (tachycardia), too slow (bradycardia), or irregular. Choice B, Bradycardia, specifically denotes a slow heart rate, while choice C, Tachycardia, refers to a fast heart rate. Choice D, Conductivity, is not the correct term to describe an abnormal heartbeat characterized by speed irregularities.