The human heart is a muscular and the most powerful organ responsible for the pumping of blood around the body. It works continuously throughout the life of a person. Living organisms cease to exist when they're heart stop functioning.
The heart is located within the chest or thoracic cavity and behind the breastbone (sternum) and between the two lobes of the lungs. Each pumping action of the heart is known as the heart beat . Each animal has a certain number of heartbeats per minutes. This can't be counted by feeling the pulse at the wrist. Man has an average of 72 heart beats per minute when at rest. This can be increased to 100 or more during activity or excitement. Small animals like rats may have 200 heartbeats per minute, where as big animals like elephants we have only about 12