ATI RN
Physical Exam Cardiovascular System Questions
Question 1 of 5
Which artery supplies the right atrium, right ventricle, a portion of the septum, SA node, AV node, and inferior portion of the left ventricle?
Correct Answer: A
Rationale: The correct answer is A: Right coronary artery. This artery supplies the mentioned structures as it branches off from the aorta and follows the coronary sulcus to reach the right side of the heart. It provides blood to the right atrium, right ventricle, part of the septum, SA node, AV node, and inferior left ventricle. The Left circumflex artery (B) mainly supplies the left atrium and lateral part of the left ventricle. The Posterior descending artery (C) typically arises from the right coronary artery and supplies the inferior part of the heart. The Aortic artery (D) is not a specific artery that directly supplies the structures mentioned.
Question 2 of 5
What is the approximate stroke volume of the heart?
Correct Answer: B
Rationale: The correct answer is B (Approximately 70 mL of blood per beat). The average human stroke volume is around 70 mL. This volume represents the amount of blood ejected by the left ventricle in each contraction. It is important to note that stroke volume can vary depending on factors such as age, fitness level, and cardiac health. Choices A, C, and D are incorrect because they do not align with the typical range of stroke volume in a healthy adult. Option A (60 mL) is slightly below the average, while options C (80 mL) and D (90 mL) are above the typical range. Therefore, the best approximation for stroke volume in the heart is around 70 mL per beat.
Question 3 of 5
What are the pressure-sensitive structures located in the aortic and carotid bodies called?
Correct Answer: A
Rationale: The correct answer is A: Baroreceptors. Baroreceptors are pressure-sensitive structures that detect changes in blood pressure in the aortic and carotid bodies. They help regulate blood pressure by sending signals to the brain to adjust heart rate and blood vessel dilation. Chemoreceptors (B) detect changes in chemical composition, not pressure. Nociceptors (C) detect pain stimuli. Mechanoreceptors (D) detect mechanical stimuli, not specifically pressure changes. Therefore, the correct answer is A as baroreceptors specifically respond to changes in blood pressure.
Question 4 of 5
Which neurotransmitter released by the parasympathetic nervous system can decrease heart rate?
Correct Answer: A
Rationale: The correct answer is A: Acetylcholine. Acetylcholine is released by the parasympathetic nervous system and acts on the heart to decrease heart rate. It binds to muscarinic receptors in the heart, leading to a decrease in heart rate through inhibition of the SA node. Norepinephrine (B) is released by the sympathetic nervous system and increases heart rate. Dopamine (C) and Serotonin (D) are not directly involved in regulating heart rate through the parasympathetic pathway.
Question 5 of 5
Which valve prevents backflow of blood into the right ventricle from the pulmonary artery?
Correct Answer: A
Rationale: The correct answer is A: Pulmonary valve. This valve prevents backflow of blood into the right ventricle from the pulmonary artery by closing when the right ventricle relaxes. The pulmonary valve ensures that blood flows in one direction, from the right ventricle to the pulmonary artery. The other choices, B: Aortic valve, C: Tricuspid valve, and D: Mitral valve, are incorrect because they are not located between the right ventricle and the pulmonary artery. The aortic valve is between the left ventricle and the aorta, the tricuspid valve is between the right atrium and ventricle, and the mitral valve is between the left atrium and ventricle.