Heart and it's function
In most animals, the heart is a muscular organ. This organ circulates blood via the circulatory system's blood arteries. [1] Pumped blood transports oxygen and nutrients to the body while transporting metabolic waste like carbon dioxide to the lungs. [2] In humans, the heart is about the size of a closed fist and is placed in the middle compartment of the chest, between the lungs. The heart is split into four chambers in humans other animals and birds: upper left and right atria and bottom left and right ventricles. [4] The right atrium and ventricle are commonly referred to as the right heart, whereas their left counterparts are referred to as the left heart. [6] In contrast, fish have two chambers, an atrium and a ventricle, whereas most reptiles have three. [5] Blood goes one way through in the healthy heart thanks to heart valves that prevent backflow. [3] The heart is surrounded by a protective sac called the pericardium, which also contains some fluid. The heart's wall i...