CMT Cardiac Anatomy and Physiology 3 — Questions and Answers
Question 1: Which structure separates the right and left ventricles?
- Interatrial septum
- Interventricular septum (Correct answer)
- Atrioventricular node
- Bundle of His
Correct answer: Interventricular septum
The interventricular septum is the muscular wall dividing the right and left ventricles, helping maintain separate systemic and pulmonary circulation pressures.
Question 2: The aortic valve opens during which phase of the cardiac cycle?
- Isovolumetric relaxation
- Ventricular filling
- Isovolumetric contraction
- Ventricular ejection (systole) (Correct answer)
Correct answer: Ventricular ejection (systole)
The aortic valve opens when left ventricular pressure exceeds aortic pressure during systole, allowing blood to be ejected into the aorta.
Question 3: Which vessel carries oxygenated blood from the lungs back to the heart?
- Pulmonary arteries
- Superior vena cava
- Pulmonary veins (Correct answer)
- Coronary sinus
Correct answer: Pulmonary veins
The four pulmonary veins carry oxygenated blood from the lungs to the left atrium, completing the pulmonary circuit.
Question 4: What is the approximate resting heart rate range considered normal for adults?
- 40–50 beats per minute
- 60–100 beats per minute (Correct answer)
- 100–120 beats per minute
- 50–60 beats per minute
Correct answer: 60–100 beats per minute
A normal resting heart rate for adults is 60–100 beats per minute; below 60 is bradycardia and above 100 is tachycardia.
Question 5: The Purkinje fibers are responsible for which function in the heart?
- Initiating the sinus impulse
- Delaying conduction at the AV node
- Rapidly conducting impulses throughout the ventricular myocardium (Correct answer)
- Repolarizing the atrial muscle cells
Correct answer: Rapidly conducting impulses throughout the ventricular myocardium
Purkinje fibers are specialized conduction cells that rapidly distribute electrical impulses through the ventricular walls to coordinate simultaneous contraction.
Question 6: Which chamber of the heart has the thickest myocardial wall and why?
- Right ventricle, because it pumps to the lungs at high pressure
- Left atrium, because it receives blood from all pulmonary veins
- Left ventricle, because it pumps against high systemic vascular resistance (Correct answer)
- Right atrium, because it receives blood from the entire body
Correct answer: Left ventricle, because it pumps against high systemic vascular resistance
The left ventricle has the thickest wall because it must generate enough pressure to overcome systemic vascular resistance and pump blood throughout the entire body.
Question 7: Blood from the superior and inferior vena cava drains into which chamber?
- Left atrium
- Right ventricle
- Left ventricle
- Right atrium (Correct answer)
Correct answer: Right atrium
Both the superior vena cava (upper body) and inferior vena cava (lower body) return deoxygenated blood to the right atrium to begin pulmonary circulation.
CMT Cardiac Anatomy and Physiology 3
Which structure separates the right and left ventricles?