CCT Cardiac Anatomy & Physiology 2 — Questions and Answers
Question 1: Which valve prevents backflow of blood from the aorta into the left ventricle?
- Mitral valve
- Tricuspid valve
- Aortic semilunar valve (Correct answer)
- Pulmonic semilunar valve
Correct answer: Aortic semilunar valve
The aortic semilunar valve closes during diastole to prevent regurgitation of blood from the aorta back into the left ventricle.
Question 2: The chordae tendineae attach the AV valve leaflets to which cardiac structure?
- Interventricular septum
- Papillary muscles (Correct answer)
- Trabeculae carneae
- Moderator band
Correct answer: Papillary muscles
Chordae tendineae are fibrous cords that connect the AV valve leaflets to the papillary muscles, preventing valve prolapse during systole.
Question 3: Which coronary artery typically supplies the sinoatrial (SA) node in most individuals?
- Left anterior descending artery
- Right coronary artery (Correct answer)
- Left circumflex artery
- Diagonal branch
Correct answer: Right coronary artery
In approximately 60% of individuals, the SA nodal artery arises from the right coronary artery (RCA).
Question 4: What is the approximate normal cardiac output at rest in a healthy adult?
- 1–2 L/min
- 3–4 L/min
- 5–6 L/min (Correct answer)
- 8–10 L/min
Correct answer: 5–6 L/min
Normal resting cardiac output is approximately 5–6 liters per minute, calculated as heart rate multiplied by stroke volume.
Question 5: Which layer of the heart wall contains the cardiac muscle cells responsible for contraction?
- Epicardium
- Pericardium
- Myocardium (Correct answer)
- Endocardium
Correct answer: Myocardium
The myocardium is the thick middle layer of the heart wall composed of cardiac muscle cells (cardiomyocytes) that generate the force of contraction.
Question 6: The fossa ovalis is a remnant of which fetal cardiac structure?
- Ductus arteriosus
- Foramen ovale (Correct answer)
- Ductus venosus
- Umbilical vein
Correct answer: Foramen ovale
The fossa ovalis is a depression in the interatrial septum that represents the closed foramen ovale, a fetal shunt that allowed blood to bypass the lungs.
Question 7: Which property of cardiac muscle allows an action potential to spread from cell to cell throughout the myocardium?
- Automaticity
- Conductivity via gap junctions (Correct answer)
- Contractility
- Excitability
Correct answer: Conductivity via gap junctions
Cardiac muscle cells are connected by gap junctions (intercalated discs) that allow ion flow and action potential propagation between cells, making the heart a functional syncytium.
CCT Cardiac Anatomy & Physiology 2
Which valve prevents backflow of blood from the aorta into the left ventricle?