While it is pretty straightforward that humans need food in order to survive, not many people are aware of the fact that deep inside our body’s core another form of nutrition takes place. That is the delivery of oxygen rich blood to our tissues, organs and cells in order for our bodies to properly function.
If our oxygen rich blood is effectively transported throughout our bodies deep to our cells, it is thanks to the presence of an intrinsic network of blood vessels. Blood vessels are typically hollow tubes that efficiently deliver blood to our bodies. They are part of the cardiovascular system responsible for the circulation of blood and they encompass arteries, veins and capillaries.
The way these arteries, veins and capillaries are displayed in our body is similar to how a tree’s roots start big and then gradually get thinner and thinner as they get farther away from the tree. The arteries are the largest blood vessels, they carry blood away from the heart, the veins are smaller than the arteries and they deliver blood back to the heart and finally the capillaries are the smallest blood vessels which link the blood from the arteries to the veins.
The largest artery of the body is the aorta which directly links blood from the heart to the body’s cells. Arteries tend to be elastic hollow tubes that expand every time that the heart pumps blood through them (systolic phase) while they constrict once the the heart relaxes (diastolic phase). Each time the heart relaxes the blood flows from the arteries into the veins. Arteries tend to get smaller as they get farther away from the heart, these smaller sized arteries are called ”arterioles”.
The Venae Cavae are the two largest veins in the body. Veins carry oxygen poor blood back to the heart where it get reoxiginated in the lungs through the pulmonary artery. Veins as well expand when blood flows through them and the expansion and contraction is what causes a ”pulse”. Veins as arteries get smaller as they get farther away from the heart, these smaller sized veins are called ”venules”.
Capillaries are the ultimate venues that deliver the blood to the body’s cells. This blood delivered to the cells is rich in oxygen,nutrients, and chemicals essential for life. Wtihin the capillaries waste products are released such as in the kidneys and in the lungs. In the kidneys waste products of the body are released and concentrated into urine to be discarded. In the lungs, capillaries deliver the waste product carbon dioxide which is exhaled and then the blood is enriched with oxygen again forming a cycle that allows circulation.
All the cells in our bodies require blood from which they must draw essential nutrients. We are composed of about 10 trillion cells that make up our skin. organs, eyes and even the enamel of our teeth! These cells are the building blocks of life and it is thanks to these cells that we are able to live our lives everyday.
