Blood Vessels

Human anatomy > Circulatory System > Blood Vessels

Vessels are characterized as hollow containers that are especially for liquids. For the human body, these hollow containers are the blood vessels. They transport blood to all parts of the human body. That being said, it is safe to claim that they are the basic components of the circulatory system. This is considered to be the most fundamental system as it enables nutrients, gases and hormones to pass to and from cells to aid body resistance against diseases and gain stable body temperature.

Blood vessels are so massive. An average child has blood vessels equivalent to a line measuring more than sixty thousand miles long. As for the adult, the line would be at about a hundred thousand miles long. 

Their huge quantity is subdivided into three major types, such as:

The arteries are responsible for carrying the blood away from the heart. They are tough tube-like structures which have smooth lining on the inside. Each artery is composed of three different layers; namely, the outer tissue, muscular middle and inner layer of epithelial cells. The reason why the arteries are very strong on the outer and middle layers is to enable them to withstand the pressure of pumping blood. The smooth layer is such so that the path of the blood would have no obstacles whatsoever.The main artery used by the heart to pump out blood is called the dorsal aorta. This divides into smaller arteries, which enable each of all the regions in the body to have fresh supply of blood. Prior to being branched into body regions, the arteries actually deliver oxygen-rich blood to the second type of blood vessels called the capillaries.

Blood vessels

The capillaries actually serve as the connectors for arteries and veins. They are very thin and fragile – with each one being equivalent to the size of one epithelial cell, about a hundred microns. This thinness allows blood cells to pass only through a single file. The exchange of oxygen and carbon dioxide in the blood cells takes place here.

The veins are like arteries, but with thinner layers because of having less tissue contents. Once they receive blood from the second component, they transport waste-rich blood to the lungs and heart. They ensure that the blood is transported properly, specifically only in one direction, by means of their valves.

Each of them has significance, such as:

The arteries are significant for measuring vital health statistics such as pulse rate and blood pressure. The former is measured through touching an artery as it keeps pace with the rhythmic contraction of the heart. The latter is done through once again touching the artery for the blood has higher pressure in it than through the veins.

Capillaries ensure that the blood cells going to veins are waste-free. Thus, only clean blood can be transported back to the lungs and heart. In the long run, this component is very vital to ensure all the parts of the body would only work with fresh blood. Moreover, they also enable the body to release excessive heat. Once ‘hot’ blood passes through them, they rapidly release the heat to the tissues.

As for the veins, they mainly allow blood to flow against gravitational force. This is vital especially when transporting blood from lower regions of the body, such as the leg area, back to the upper region where the heart is. The vein valves provide support to the blood for it to safely climb back to the heart.

By knowing how blood vessels work for your body, you are now capable of making them function better.

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