my./health/articles/17059-heart-blood-vessels-how-does-blood-travel-through-your-body Heart and blood vessels: How does blood travel through your body.anatomy/cardiovascular/blood/classification.html Classification and structure of blood vessels.You can learn more about how we ensure our content is accurate and current by reading our editorial policy. Healthline has strict sourcing guidelines and relies on peer-reviewed studies, academic research institutions, and medical associations. The heart provides the force to circulate blood through the cardiovascular system. The heart has four chambers: the right atrium, right ventricle, left atrium, and left ventricle. The primary function of capillaries is the exchanging of materials, like oxygen, between the blood and tissue cells. They connect between the arteries (which carry blood away from the heart) and the veins (which return blood to the heart). Capillaries are the smallest and most numerous of the blood vessels. Systemic veins carry low-oxygen blood from the body to the right atrium of the heart. The pulmonary veins carry oxygenated blood from the lungs to the left atrium of the heart. Systemic arteries transport oxygenated blood from the left ventricle of the heart to the rest of the body. The pulmonary arteries carry low-oxygen blood from the right ventricle of the heart to the lungs. It does this through thousands of miles of capillaries between the arteries and the veins. The cardiovascular system keeps a continuous and controlled movement of blood that delivers nutrients and oxygen to every cell in the body. They’re all connected to a muscular pump called the heart. The cardiovascular system is a closed system of vessels called arteries, veins, and capillaries. They fight gravity to prevent the backflow of blood.Īrteries don’t need valves because the pressure from the heart keeps the blood flowing through them in one direction. Theses valves are particularly important in the legs and arms. Veins need valves to keep the blood flowing toward the heart. Its consistency varies based on the type of blood vessel. This layer is made of elastic fiber and collagen. The inner layer of the blood vessel wall is called tunica intima. This layer is thicker in arteries and thinner in veins. It’s made of smooth muscle and elastic fibers. The middle layer of the walls of arteries and veins is called the tunica media. They stretch enough to be flexible while maintaining stability under the pressure of blood flow. These fibers enable the veins and arteries to stretch a limited amount. It’s mostly composed of collagen and elastic fibers. Tunica adventitia (tunica externa) is the outer layer of a blood vessel, including arteries and veins. The walls of veins and arteries are both made up of three layers:
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |