What is the Meaning & Definition of blood vessel


The blood vessels are tubular structures that have the function of transporting blood and from the heart to all tissues of the body.
They are two independent types among themselves, the arteries that carry blood from the heart to the tissues and veins that return blood from the tissues back to the heart. Communication between the arteries and veins occurs through very small-caliber vessels known as capillaries.

The blood vessels are composed of different layers

The wall of the blood vessels is made up of different layers, part internal is endothelium, in the Center the adventitia layer coating muscle and superficially.
The endothelium is a structure formed by a layer of cells that serves important functions for the organism, releases a series of substances that regulate the tone of the blood vessel, as well as various factors that promote blood clotting and are also capable of modular it.
The muscular layer consists of smooth muscle and elastic fibers, elastin-mainly, while coating the outer or adventitia is constituted by supporting tissue. In the case of the arteries of large caliber in this last layer are the nerves that allow contraction or relationship of the muscular layer as well as the blood vessels that provide oxygen and nutrients to the arteries, these tiny vessels contribution is known as vasa vasorum and their involvement is common in diseases such as diabetes being the cause of vascular disorders that can be seen in this disease.

The arteries and veins have different structures

The arteries and veins have marked differences in its structure, which is related to the role of each type of blood vessel must carry out.
Arteries. Such vessels have a more developed than the veins muscular layer, this allows them to have some elasticity that facilitates that she is procedure and contract to push blood through the circulatory system, this cycle of contractions and relaxations can be perceived to the touch surface arteries and it is what is known as pulse. The muscular layer gives also the arterial blood vessels some resistance that constitute the diastolic blood pressure.
Veins. Veins must be the blood back to the heart, this function does not require a muscular layer that offers resistance so the veins are thinner than the arteries; the veins have rather a system of valves in the form of nests of swallow that prevents the flow backward, especially at the level of the legs where gravity favors this phenomenon.
Article contributed by the team of collaborators.