The trabeculae carneae also serve a function similar to that of papillary muscles in that their contraction pulls on the chordae tendineae, preventing inversion of the mitral (bicuspid) and tricuspid valves towards the atrial chambers, which would lead to subsequent leakage of the blood into the atria.

Subsequently, question is, is the right atrium muscular? Right Atrium. The right atrium receives deoxygenated blood from the superior and inferior vena cavae, and from the coronary veins. Atrium proper – located anterior to the crista terminalis, and includes the right auricle. It is derived from the primitive atrium, and has rough, muscular walls formed by pectinate muscles

Also to know is, what is the function of the papillary muscles?

The papillary muscles are muscles located in the ventricles of the heart. They attach to the cusps of the atrioventricular valves (also known as the mitral and tricuspid valves) via the chordae tendineae and contract to prevent inversion or prolapse of these valves on systole (or ventricular contraction).

How does the external appearance of the atria differ from that of the ventricles?

The ventricles of the heart have thicker muscular walls than the atria. This is because blood is pumped out of the heart at greater pressure from these chambers compared to the atria. The left ventricle also has a thicker muscular wall than the right ventricle, as seen in the adjacent image.