Arteries and Veins Facts

Welcome to MooMooMath and Science In this video I would like to talk about arteries and veins. Arteries are blood vessels that carry blood away from the heart. Arteries carry blood that is rich with oxygen except for the pulmonary artery. If you take a look at the flow of blood around the heart you will notice that the pulmonary artery carries blood to the lungs. This blood is oxygen poor. However when this blood travels through the lungs and back to the heart it has lots of oxygen. Next this oxygen rich blood leaves the heart through an artery and flows throughout the body. Arteries have three main layers. They have an outer layer of connective tissue, a middle layer of smooth muscle, and a very thin layer of endothelial cells. Blood flows through the arteries under high pressure and arteries do not have valves. Veins carry blood towards the heart. Veins are oxygen poor except for the pulmonary vein. Take a look at the heart again and the flow of blood. The pulmonary vein carries blood from the lungs to the heart and this blood has lots of oxygen. A vein has three layers, connective tissue, smooth muscle, but is not as thick as an artery, and a thin layer of endothelial cells. Veins have valves to help prevent the flow of blood backwards and veins are not as flexible as arteries nor is the muscular middle layer as thick. Arteries and veins are connected by small vessels called capillaries. I hope that helps with your understanding of arteries and veins and MooMooMath uploads a new math and science video everyday. Please subscribe and share