Artery/veins
• Arteries and veins are the two major blood capillaries which are responsible for the supply of the blood to the whole body, their vast connections and networks have enabled an efficient supply of blood to the whole body from the heart. The oxygenated blood from the heart is supplied to the whole body by the arteries and the deoxygenated blood is collected from all the parts and brought back to the heart from the veins. Because of the difference in the function of the two blood vessels there are alot other differences between the two as stated
• The general structure of the walls of the blood vessels is the same but of course because of different functions there are some compositional differences. The walls are generally made up of muscular and elastic tissues , but for the arteries the muscular tissues are in higher composition, making the walls of arteries much thicker then the walls of the veins. The reason is simple: Blood is directly pumped from the heart into the aorta which further branches into arteries. The pressure of blood in the heart when it enters the aorta is the highest and that’s the requirement so the blood can reach all the organs. So to bear that high pressure without any damage to the vessels ; they need to have thick muscular and elastic walls. On the contrary the pressure in the veins is not high and the blood is flowing normally, so there isn’t any need for thick walls , accounting for the thin walls with less muscular tissues. There is a narrow lumen which complements the pressure flow of the blood in the arteries, while the lumen of the veins is wide.
• The arteries are embedded into the body , deeply, while the veins are visible through the skin, with the blue oxygenated blood running through it. The arteries carry red oxygenated blood, while the veins carry blue deoxygenated blood.
• The direction of flow of blood through the arteries is away from the heart while the veins carry the blood toward the heart. All the veins coming from different organs join together to make the superior and inferior vena cava that pour the blood into the right atrium
• The pressure of blood as stated above is high in the arteries and low in the veins.
• As the arteries carry oxygenated blood they have high levels of oxygen , while the venous blood has low oxygen level. The levels of carbon dioxide are opposite, high in venin low in arteries.
• There are no valves in the arteries as the blood pressure is high and there are little chances of flow back. But in the veins we will find valves that prevents the backflow of the blood ,as it flows slowly
• Due to the high blood pressure in the arteries and since they are responsible for the transportation of oxygenated blood, these vessels are more susceptible to diseases, that includes any damage to the vessels, thickening which can lead to diseases like arteriosclerosis, angina. Veins are less susceptible to diseases ,still there are some major disorders for it.
