What separates the right and left ventricles?

What separates the right and left ventricles?

• A. Interatrial septum
• B. Interventricular septum
• C. Fossa ovalis
• D. Papillary muscles

Answer: (B)

The key idea is that the structure separating the right and left ventricles is the interventricular septum. This muscular wall forms the boundary between the two ventricular chambers, keeping deoxygenated blood in the right ventricle from mixing with the oxygenated blood in the left ventricle. It has a thick muscular portion and a small membranous portion near the heart’s base, and it even houses part of the heart’s conduction system, helping coordinate ventricular contraction. The other structures mentioned don’t separate the ventricles: the interatrial septum divides the atria, the fossa ovalis sits on the interatrial septum as a remnant of the foramen ovale, and the papillary muscles are inside the ventricles anchored to the chordae tendineae, not separating the ventricles.

The key idea is that the structure separating the right and left ventricles is the interventricular septum. This muscular wall forms the boundary between the two ventricular chambers, keeping deoxygenated blood in the right ventricle from mixing with the oxygenated blood in the left ventricle. It has a thick muscular portion and a small membranous portion near the heart’s base, and it even houses part of the heart’s conduction system, helping coordinate ventricular contraction. The other structures mentioned don’t separate the ventricles: the interatrial septum divides the atria, the fossa ovalis sits on the interatrial septum as a remnant of the foramen ovale, and the papillary muscles are inside the ventricles anchored to the chordae tendineae, not separating the ventricles.