What structure in the heart prevents backflow of blood?

The structure in the heart that plays a crucial role in preventing the backflow of blood is the valves. The heart consists of four main chambers: two atria and two ventricles, which are separated by these valves. During the cardiac cycle, when the heart contracts to pump blood, the valves ensure that blood flows in one direction—forward into the arteries and out to the body or lungs—preventing it from flowing backward into the chambers.

There are two primary types of valves in the heart: the atrioventricular valves (tricuspid and mitral) located between the atria and ventricles, and the semilunar valves (pulmonary and aortic) located between the ventricles and the arteries exiting the heart. These valves open and close in response to pressure changes as the heart beats, which effectively prevents any regurgitation of blood.

The atria, septum, and myocardium do not serve this specific function of preventing backflow. Atria are the receiving chambers of the heart, the septum is a wall that divides the right and left sides of the heart, and myocardium is the muscular tissue of the heart responsible for contraction. Their functions are important for overall heart operation, but when it comes