Anatomy Exam Anatomy of the Heart 5 — Questions and Answers
Question 1: Which structure marks the external boundary between the atria and ventricles on the surface of the heart?
- Anterior interventricular sulcus
- Coronary sulcus (atrioventricular groove) (Correct answer)
- Posterior interventricular sulcus
- Crista terminalis
Correct answer: Coronary sulcus (atrioventricular groove)
The coronary sulcus (atrioventricular groove) is the external groove encircling the heart that separates the atria from the ventricles.
Question 2: The apex of the heart is formed by which chamber, and where does it point?
- Right ventricle; points superiorly and to the right
- Left ventricle; points inferiorly, anteriorly, and to the left (Correct answer)
- Left atrium; points posteriorly and to the left
- Right atrium; points inferiorly and to the right
Correct answer: Left ventricle; points inferiorly, anteriorly, and to the left
The apex of the heart is formed by the left ventricle and points inferiorly, anteriorly, and to the left, typically located at the 5th intercostal space in the midclavicular line.
Question 3: Which heart valve is best auscultated at the 5th left intercostal space, midclavicular line?
- Aortic valve
- Pulmonary valve
- Mitral valve (Correct answer)
- Tricuspid valve
Correct answer: Mitral valve
The mitral valve (left AV valve) is best heard at the cardiac apex — 5th left intercostal space at the midclavicular line.
Question 4: The great cardiac vein runs in which sulcus?
- Posterior interventricular sulcus
- Right atrioventricular sulcus
- Anterior interventricular sulcus (Correct answer)
- Oblique sinus
Correct answer: Anterior interventricular sulcus
The great cardiac vein ascends in the anterior interventricular sulcus alongside the left anterior descending artery before continuing in the coronary sulcus.
Question 5: Which portion of the interventricular septum is primarily membranous (fibrous) rather than muscular?
- The large inferior portion
- The small superior portion near the fibrous skeleton (Correct answer)
- The middle third
- The apical portion
Correct answer: The small superior portion near the fibrous skeleton
The membranous part of the interventricular septum is a small, thin fibrous area located superiorly near the fibrous skeleton; the remaining majority is thick muscular septum.
Question 6: During ventricular systole, which valves are open?
- Mitral and tricuspid valves
- Aortic and pulmonary valves (Correct answer)
- All four valves simultaneously
- Only the mitral valve
Correct answer: Aortic and pulmonary valves
During ventricular systole, increased intraventricular pressure closes the AV valves and opens the semilunar valves (aortic and pulmonary), ejecting blood into the great vessels.
Question 7: Which structure transmits the cardiac impulse from the atria to the ventricles through the fibrous skeleton?
- SA node
- Purkinje fibers
- Atrioventricular (AV) node and bundle of His (Correct answer)
- Moderator band
Correct answer: Atrioventricular (AV) node and bundle of His
The AV node collects the impulse from the atria, delays it briefly, and then conducts it through the bundle of His — the only electrical pathway piercing the fibrous skeleton into the ventricles.
Anatomy Exam Anatomy of the Heart 5
Which structure marks the external boundary between the atria and ventricles on the surface of the heart?