Final answer:
The distinctive heart sounds are best heard at the heart's apex. The first heart sound (S1) occurs during ventricular systole and the second (S2) during ventricular diastole. The septum has no openings in adults, except for the fossa ovalis in the interatrial septum. Option c.
Step-by-step explanation:
The area of the heart where heart sounds are heard most distinctively is the apex.
Understanding Heart Sounds and the Cardiac Cycle
In a healthy heart, there are typically two audible heart sounds: S1 and S2. The first heart sound, S1, is produced by the closing of the atrioventricular valves during ventricular systole, which is the contraction of the ventricles. The second heart sound, S2, occurs during ventricular diastole, when the semilunar valves close.
Septa of the Heart and Blood Flow
The septa of the heart, specifically the interatrial septum, play an important role in directing blood flow. In adults, there should typically be no openings within the septum, with the exception of the fossa ovalis, which is a remnant of the fetal circulation located in the interatrial septum. The chamber that initially receives blood from the systemic circuit is the right atrium.
Heart Valve Function and Heartbeat Origin
The mitral valve, an atrioventricular valve, separates the left atrium from the left ventricle. It is false to say that blood travels through the bicuspid valve to the left atrium, as blood actually flows from the left atrium to the left ventricle via the mitral valve. A healthy heartbeat originates from the sinoatrial (SA) node, which acts as the heart's natural pacemaker.