The Circulatory System’s blood vessels could stretch around our Earth’s equator twice

Did you know that the blood vessels in a single human body could get around our earth’s equator two times?

Blood distributes substances necessary for a normal functioning of the human organism. The organ that ensures that our blood keeps flowing is our heart, which pumps blood throughout our whole body. Our blood vessels are actually pipes full of blood. Various nutrients, such as oxygen or sugar, permeate blood vessels into cells that they “feed”. This is the reason why we need blood vessels to flow around all the 100 billion cells in our bodies. Blood gets oxygenated in our lungs. Such oxygenated blood flows into our heart and our heart sends it to the rest of the body to distribute the oxygen to all our cells. Blood vessels in our bodies that contain oxygenated blood are called arteries. Arteries extent from our heart to their target cells, where nutrients are transmitted. When this happens, the blood becomes de-oxygenated and the vessels that contain this blood are called veins. Veins collect the de-oxygenated blood and transport it back to our lungs. Some vessels are unable to supply themselves with the blood that flows in them, but there are also so-called vessels of vessels that bring blood to the surface of the vessel walls and supply it as well. If we add up the lengths of all arteries, veins and vessels in a human body we will get a staggering number of 100 000 kilometers. If we stretched all these vessels, they could circle the earth at its equator twice.

This issue may be studied in the field of:

Medicine

Biology

Author: Zuzana Bogárová, FMFI UK, P-mat n.o.

Photo: http://fotky-foto.sk/

Published by: ZČ

Translated by: Dorota Jagnešáková