This article is about Anatomy and physiology of the body: the heart. The heart is an organ composed of muscle. It functions similarly to other smooth muscle in the body, working involuntarily thanks to influence from the autonomic nervous system. The function of the heart is to distribute blood throughout the body, which is used to provide oxygen to all of the body’s cells. Inside the chest cavity, the heart is located towards the front in the lower left area of the central chest area (anterior meditational cavity), above the diaphragm, with roots behind the fifth and sixth ribs (costal V and VI), approximately two finger widths below the mammary papilla.
The main parts of the heart
In the anatomy and physiology of the body: the heart, we can also see that the heart is divided into four main parts or chambers, namely the Right and Left Atriums and the Right and Left Ventricles. The Right Atrium receives de-oxygenated blood rich in CO2 from the body coming through the superior and inferior vena cava. The senatorial node transfers an impulse that causes the muscle tissue in the atrium to contract in a coordinated wave-like manner.
The tricuspid valve which separates the right atrium from the right ventricle opens to let the de-oxygenated blood flow from the right atrium into the right ventricle. In turn, the right ventricle receives this CO2-rich blood as the right atrium contracts. The pulmonary valve leading from the ventricle into the pulmonary artery is closed, allowing the right ventricle to fill with blood.
Once the ventricle is full, the tricuspid valve closes again and the semi-lunar pulmonary valve opens. The closing of the tricuspid valve is necessary to prevent blood from flowing back into the right atrium and the opening of the pulmonary valve allows blood to flow to the lungs through the pulmonary artery.
The Left Atrium receives oxygenated blood from the lungs through the pulmonary vein. As the contraction moves through the atrium, triggered by the senatorial node, the blood moves into the left ventricle through the mitral valve. In this way, the left ventricle receives oxygen-rich blood from the left atrium. The aortic valve is closed, preventing blood from flowing into the aorta and allowing the left ventricle to fill with blood. Once the ventricle is full, the mitral valve closes to prevent blood from flowing back into the left atrium, and the aortic valve opens so that oxygenated blood can flow into the aorta and onward to all parts of the body.