Blood Circulation

Howdy there,

I hope everyone is doing well. As you may or may not know, I look at my blog stats to see what people have been coming to my site for, in an effort to serve my readers. I have noticed that recently people have been coming to my blog looking for the general path of blood as it circulates throughout the body so I will post on that tonight.

Circulation of blood, as the name says, doesn't begin at a specific point because it is a circuit. It is constantly flowing in a circle, so I will arbitrarily begin with the right atrium. The right atrium receives unoxygenated blood from the vena cava and then contracts, forcing the blood through the tricuspid valve into the right ventricle. The right ventricle then contracts forcing the blood through the pulmonary valve and on into the pulmonary artery (the only artery in the body that carries unoxygenated blood; an artery is just a vessel that carries blood away from the heart). The pulmonary artery carries the blood into the lungs (the capillaries in the alveoli) where the blood becomes oxygenated. The newly oxygenated blood is then carried back to the heart via the pulmonary vein (conversely, the only vein in the body that carries oxygenated blood; veins merely carry blood back to the heart) and then enters the left atrium. The left atrium then contracts forcing the blood through the bicuspid (also known as the mitral) valve and on into the left ventricle. The left ventricle then contracts and forces the oxygenated blood through the aortic valve and on into the aortic arch (which leads into the aorta) where the blood is pushed into the systemic circulation. After flowing into smaller arteries, then arterioles, capillaries, venules, and then into the veins, the now unoxygenated blood (it has already delivered oxygen to the tissues) flows into the inferior and superior vena cavae which return the blood to the right atrium where the circuit continues all over again.

I hope this helps.

Good luck students!
Bravomedic out.