What separates the right and left sides of the heart?

The septum is the structure that separates the right and left sides of the heart, playing a crucial role in maintaining the distinct functions of each side. The heart is essentially divided into two halves: the right side, which receives deoxygenated blood and pumps it to the lungs for oxygenation, and the left side, which receives oxygenated blood from the lungs and circulates it to the rest of the body. The septum, made up of muscle tissue, ensures that these two blood flow systems do not mix, thus maintaining efficient circulation and proper oxygenation of blood.

This separation is vital for the heart's function as it allows for effective pumping and routing of blood according to the body’s needs, which is key in maintaining the overall health and efficiency of the cardiovascular system.