Your body’s circulatory system is comprised of your heart and a network of blood vessels. Blood is sent through this network to the furthest reaches of your body, supplying your cells and organs with oxygen-rich blood. There are four primary sub-networks that each play an important role in this process: the arterial, venous, capillary, and pulmonary systems.

In this article, we’ll take you through the entire structure. You’ll learn the pathways through which your blood travels along with the contribution of your heart and each of the four sub-networks.

Arteries

Blood flows from your heart through your pulmonary and aortic arteries. The pulmonary arteries deliver blood from your right ventricle to your lungs where the blood is enriched with oxygen before being returned to your heart. The aorta carries oxygenated blood from your left ventricle, making the blood available to the rest of your body.

Your pulmonary and aortic arteries end in branches of arterioles. These are small blood vessels that are both flexible and strong, and help regulate the amount of blood that circulates throughout your body.

Veins

Your veins include the vena cava and pulmonary veins. Their job is simple: to bring oxygen-poor blood to your heart. While they are flexible enough to accommodate an increase in the amount of blood flowing through them, their walls are less durable than those of your arteries.

Capillaries

Your capillaries are part of a network that connects your arteries and veins. They are very small and are responsible for delivering oxygen and nutrients to cells and organs throughout your body.

While your arteries and veins have strong, thick walls, your capillaries do not. Their walls are so thin that they allow oxygen and nutrients to pass through them. They also allow waste material such as carbon dioxide to pass through. Capillaries receive carbon dioxide from your body’s tissues and send it to your lungs for expulsion.

Pulmonary Circulation

Your pulmonary circulatory system includes the arterial and venous networks. As described above, oxygen-poor blood is sent from your right ventricle to your lungs through your pulmonary arteries. Once the blood has been enriched with oxygen, it is sent back to your heart’s left atrium through your pulmonary veins. When the left atrium contracts, blood flows through the mitral valve (a one-way valve) into your left ventricle. When your left ventricle contracts, the oxygen-rich blood flows through the aortic valve into the aorta. The aorta carries the blood throughout your body.

Your heart and circulatory system, along with its sub-networks of arteries, veins, and capillaries, ensure that oxygen-rich blood reaches every part of your body. Your cells and organs must have a constant supply of oxygen in order to function properly. Once they receive oxygen from your blood, the blood is pumped back to your lungs through your heart and circulatory system to be oxygenated again. Though few of us think about this process, it is what keeps us alive and healthy.

In Virginia finding the right doctor for cardiac surgery or vascular surgery is crucial.