Heart as Functional Syncytium
Heart is a major muscular organ in humans and animals. It plays a crucial role in supply of blood, a fluid connective tissue to the various parts of the body. It provides the body with oxygen and nutrients and also directs in the removal of metabolic wastes. Heart is divided into four chambers: upper left and right atria and lower left and right ventricles. Heart consists of heart valves which prevent the backflow. The wall of heart consists of three layers namely epicardium, endocardium and myocardium. The heart pumps the blood with the help of a rhythm proposed by a group of pacemaking cells in sinoatrial node. This causes contraction of heart and generates a current which travels along the conduction system of heart. During this process the blood low in oxygen enters the heart where the oxygen is used and gets metabolized to carbon dioxide and is transferred to lungs.