The heart is positioned behind the breastbone, between two lungs, and somewhat to the left of the center in humans.
The human heart is a fist-sized hollow muscular organ composed of specific cell types that pump blood via the circulatory system.
It is the primary organ of the human circulatory system. Amphibians, reptiles, birds, and mammals' hearts have evolved from a single pump to a double pump that circulates blood.
Vessels of heart:
The superior and inferior vena cava deliver deoxygenated blood flow from the body into the right atrium.
The aorta directs oxygen. The left ventricle delivers oxygen-rich blood to the body.
Pulmonary veins – transport oxygen-abundant blood to the left atrium.
The pulmonary artery transports deoxygenated blood from the right ventricle to the lungs.
