It is one of the principal organs of the human being and responsible for getting the blood to all parts of the body through various blood vessels. The latter form the heart and cardiovascular system.

It is a muscular organ that performs continuous movements contraction and relaxation in order to pump blood, and bring oxygen to all cells.

Situated in the chest, where it is protected by the ribsThey are usually located on the left side of the rib cage.

Parts of Herat

The heart is divided into four parts: two atria located on the top and two ventricles, at the bottom. The atria are separated from the ventricles through two valves receiving the names of mitral and tricuspid.

The blood enters the heart through the atria and ventricles is expelled by communicated with the arteries through the aortic and pulmonary valve.

At the heart also can be distinguished as follows layers:

·  Pericardio: is an outer layer that envelops the heart.

·  Myocardium: is the muscle itself.

·  Endocardio: is the most internal heart.

Heart Operation

To pump blood laden with oxygen to all parts of the body and return to pick it up laden with carbon dioxide, the heart muscle fulfillment of contraction and relaxation movements that are called beats.

During the systole the heart is contracted and the blood around the body is succionada toward himIn diastole cardiac muscle relaxes and oxygenated blood is expelled forcefully.

Blood Circulation

Blood loaded oxygen out of the right ventricle through the aorta vein to reach all parts of the body. When the heart becomes to enter the blood returns again to the heart filled with carbon dioxide.

This blood enters through the right atrium and is expelled through the right ventricle to the lungs where it will be purified. They carbon dioxide is exchanged for oxygen.

The oxygenated blood to the heart returns to the left atrium to start again its journey through the entire body through the left ventricle.