Heart

 What is the heart?

the heart, one of the most vital organs of the human body, is a muscular organ with a circulatory system, which is responsible for pumping life-sustaining blood through the blood vessels spread throughout the body, by repeated, rhythmic contractions. from the moment it begins beating, until the moment it stops, the human heart works tirelessly.


where in the human body is the heart located?

in the human body, the heart is located a little to the left of the middle of the chest, behind the breastbone, and is well protected by the rib cage. it is placed anterior to the vertebral column and posterior to the sternum or breastbone.



what is the how many parts does a human heart have? human heart?

a normal human heart is about the size of a clenched fist and it weighs approximately 250 to 300 grams in females and 300 to 350 grams in male. right from birth, as the body develops, the heart grows at the same rate as the fist.


what is the internal structure of the heart?

the heart has three layers. the smooth, inside layer of the heart is called the endocardium and is in contact with the blood that the heart pumps. the middle layer is called the myocardium and it composed of cardiac muscle which contracts. the myocardium is surrounded by a fluid-filled sac called the pericardium. the outer layer is called the epicardium, or visceral pericardium, sins it is also the inner wall of the pericardium. the endocardium merges with the inner lining (endothelium) if blood vessels and covers the heart valves. the right side and the left side of the heart are separated by a thick wall of muscle called the septum.


how many parts does a human heart have?

A human heart has four chambers: the two upper chambers- the left atrium and the right atrium-are also called superior atria; and the two lower chambers- the right and left ventricles-are also called inferior ventricles. Doctors commonly refer to the right atrium and right ventricle together as the right heart and to the left atrium and left ventricle as the left heart.


what do the left and right hearts do?

The right heart receives deoxygenated blood from all parts of the body and pumps it to the lungs, while the left heart receives oxygenated blood from the lungs and pumps it to the rest of the body.



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