Explain the structure of human heart

Heart is the central organ for pumping the blood throughoutt he body. It is located in the chest cavity with its lower part pointing towards the left. Its size is that of the person’s fist. 

•  It pumps blood rich in carbon dioxide to the lungs and oxygen-rich blood to other parts of the body. 
•  The heart consists of four chambers namely atria and ventricles. The two upper chambers of the heart are known as the atria. The two lower chambers of the heart are the ventricles.
•  The deoxygenated blood is completely separated from the oxygenated blood completely. The atria and ventricles are separated by many types of valves which prevent the mixing up of pure blood from that of impure blood. 
•  Heart is made up of strong cardiac muscles. The rhythmic contraction and relaxation of the heart constitutes heartbeat.
•  Heartbeat can be recognized by placing the palm on the left side of the chest. Stethoscope is a device that amplifies the sound of your heartbeat.
•  The pressure applied by blood on the walls of an artery at a particular part is the pulse. The number of times the heart beats in a minute is the same as the pulse rate.The ideal pulse rate is 70 to 80 per minute.