What are the four chambers of the heart made of?

Answer 1

The heart is comprised of the left and right atria and the left and right ventricles. The atria pump blood to the lungs, where it is oxygenated. The oxygenated blood then returns to the heart, where the ventricles pump it to the rest of the body. They are made of cardiac muscle, which is branched, striated and contains intercalated discs, which coordinate rhythmic movement. The walls of the atria are thinner, due to the relatively short distance blood must travel to the lungs, while the ventricle walls are thicker and able to provide a stronger push for blood to travel through the body.