Monday, December 5, 2011

Human Heart - Function

The heart is located inside the human body.  It is one of the most important organs in the entire human body. The heart is a myogenic muscular organ found in all animals with a circulatory system (including all vertebrates), that is responsible for pumping blood throughout the blood vessels by repeated, rhythmic contractions. The heart pumps the blood, which carries all the vital materials which help our bodies function and removes the waste products that we do not need. For example, the brain requires oxygen and glucose, which, if not received continuously, will cause it to lose consciousness. Normal human beings are beating approximately 72 times per minute of our lives.

Hearts is protected by cavity. There are three layers made the wall of the heart.  The cavity is divided into four chambers. Upper chambers are called the right and left atria, and lower chambers are called the right and left ventricles.

Human Heart

1. Left Atrium: The left atrium is one of the four chambers in the human heart. It
receives oxygenated blood from the pulmonary veins, and pumps it into
the left ventricle, via the mitral valve. 

2. Right atrium: The Right atrium  is one of four zin the hearts of mammals (including humans) and archosaurs (which include birds and crocodilians). It receives
deoxygenated blood from the superior and inferior vena cava and the
coronary sinus, and pumps it into the right ventricle through the tricuspid valve. Attached to the right atrium is the right auricular appendix.

3. Left ventricle: The left ventricle is one of four chambers (two atria and two ventricles) in the human heart. It receives oxygenated blood from the left atrium via the mitral valve, and pumps it into the aorta via the aortic valve.

4. Right ventricle: The right ventricle is fourth chambers in the human heart. It receives deoxygenated blood from the right atrium via the tricuspid valve, and pumps it into the pulmonary artery via the pulmonary valve and pulmonary trunk.  It is triangular in shape, and extends from the right atrium to near the apex of the heart. 

Function of Heart:

In mammals, the function of the right side of the heart (see right heart) is to collect de-oxygenated blood, in the right atrium, from the body (via superior and inferior vena cavae) and pump it, through the tricuspid valve, via the right ventricle, into the lungs (pulmonary circulation) so that carbon dioxide can be dropped off and oxygen picked up (gas exchange). This happens through the passive process of diffusion. The left side (see left heart) collects oxygenated blood from the lungs into the left atrium. From the left atrium the blood moves to the left ventricle, through the bicuspid valve, which pumps it out to the body (via the aorta). On both sides, the lower ventricles are thicker and stronger than the upper atria. The muscle wall surrounding the left ventricle is thicker than the wall surrounding the right ventricle due to the higher force needed to pump the blood through the systemic circulation.

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