Explain the structure of the heart and relate the structure to its function

In the heart there are 4 chambers; the upper 2 chambers are called the atria and the bottom two chambers are called the ventricles. The right and the left side of the heart are separated by the interventricular septum. There are 4 valves in the heart. 2 valves between the atria and the ventricles and 2 valves between the ventricles and the arteries that leave the heart. Valves prevent back flow of blood. The heart itself needs its own blood supply for oxygen and nutrients as it is a muscle, so is supplied by the coronary arteries.
The atria receive blood from veins and the ventricles push blood out of the heart into arteries. The right atrium receives deoxygenated blood from the body and the right ventricle pushes this deoxygenated blood to the lungs where it receives oxygen. The left atrium receives oxygenated blood from the lungs and the left ventricle pushes this oxygenated blood to the body. The left ventricle is thicker than the right ventricle as it takes more force to push blood to the body compared to the lungs.