The heart is a hollow pear-shaped muscular organ placed between the lungs in the middle of the chest that pumps blood through the body, supplying cells with oxygen and nutrients. It is attached to the breastbone by special connective tissues called ligaments. The apex (blunt point of the lower edge of the heart) lies on the diaphragm, pointing toward the left. The apex pulses with every beat of the heart. This is what you feel when you hold your hand to your heart. The heart has four cavities: a small upper cavity (atrium) and a large lower cavity (ventricle) on each side. The adult human heart is approximately the size of a fist. In an average adult, it is about five inches long and three and a half inches across at its broadest part, and it weighs less than a pound. Research Heart
Abbreviations
Medicine
Research Heart