Explanation:
The heart can be found at the center of the chest, underneath the sternum in a thoracic compartment. It is made up of four chambers and several valves that regulate the normal flow of blood within the body.
Two chambers called atria are located in the upper portion of the heart and receive oxygen-free blood. The valves that separate these chambers are called atrioventricular valves which is composed of the tricuspid valve on the left and the mitral valve on the right.
On the other hand, ventricles are chambers found on the lower portion of the heart; they pump oxygen-enriched blood into all organs of the body, reaching even the smallest cells. Similar to the atria, the ventricular chambers are also separated by valves. Collectively-termed as semilunar valves, these are comprised of the pulmonary and aortic valve.
The heart also has a wall that is composed of three layers: the outer layer epicardium (thin layer), the middle layer myocardium (thick layer), and the innermost layer endocardium (thin layer). The myocardium is think because it is made up of cardiac muscle fibers.
The structure of the heart is made more complex because of the mechanisms that allow blood to be distributed throughout the body and to return into the heart. Facilitating this continuous process are two types of blood vessels: veins and arteries (16jacktwinwritters). The vessels that bring oxygen-free blood back into the heart are called veins; those that bring oxygen-rich blood away from the heart and to other body parts are called arteries. Functioning in the left ventricle, the largest artery is called aorta. The aorta is considered a main artery in the body. It further splits into two smaller arteries called common iliac arteries.
With regular functioning, the heart is continuously able to supply sufficient amount of oxygen to all parts of the body.
