Apply market research to generate audience insights. Measure content performance. Develop and improve products. List of Partners vendors. Arteries are blood vessels that carry blood away from the heart to the rest of the body. They are shaped like tubes and branch into arterioles to reach the organs and tissues. The pumping contractions of the heart propel the blood through the arteries. The main artery of the systemic circulation is the aorta.
It is attached to the left ventricle of the heart and carries oxygenated blood. The aorta branches into arteries that go to different organs and parts of the body. You can feel your pulse in an artery such as the carotid artery in the neck or the radial artery in the wrist. The pulmonary artery differs from the others in that it is attached to the heart's right ventricle and carries blood that is poor in oxygen to the lungs.
There, it branches into arterioles and capillaries so the blood can take on oxygen before returning to the heart via the pulmonary vein. This oxygenated blood enters the left atrium and is pumped to the left ventricle and out through the aorta. Arteries contain a high percentage of a special type of muscle, called smooth muscle, that can be controlled by hormones and special signals from the nervous system. The outer layer of an artery is made of collagen fibers.
The middle layer has smooth muscle and elastic fibers. The inner layer is the lining called the endothelium. Blood travels through the hollow center of the arteries. If this hollow center becomes constricted due to overdevelopment of the muscle or the formation of plaques, it can raise blood pressure.
Plaque also makes the arteries less flexible. If an artery ruptures or is blocked, such as in a stroke or heart attack, the tissues that it normally supplies will die.
The thick, strong walls of arteries make them able to resist the high pressures that exist near the heart. All of the major organs in the body have their own special kind of arteries which are uniquely structured to deliver the supplies needed. The largest artery is the aorta, which connects to the heart and picks up oxygenated blood from the left ventricle. The only artery that picks up deoxygenated blood is the pulmonary artery, which runs between the heart and lungs.
Capillaries The arteries eventually divide down into the smallest blood vessel, the capillary. Capillaries are so small that blood cells can only move through them one at a time.
Oxygen and food nutrients pass from these capillaries to the cells. Capillaries are also connected to veins, so wastes from the cells can be transferred to the blood.
Veins Veins have one-way valves instead of muscles, to stop blood from running back the wrong way. Generally, veins carry deoxygenated blood from the body to the heart, where it can be sent to the lungs. The exception is the network of pulmonary veins, which take oxygenated blood from the lungs to the heart. Blood pressure Blood pressure refers to the amount of pressure inside the circulatory system as the blood is pumped around.
Common problems Some common problems of the circulatory system include: Aneurysm — a weak spot in the wall of an artery Atherosclerosis — a narrowing of the arteries caused by plaque deposits Heart disease — lack of blood supply to the heart because of narrowed arteries High blood pressure — can be caused by obesity among other things Varicose veins — problems with the valves that stop blood from running backwards.
Where to get help Your doctor In an emergency, always call triple zero Things to remember The circulatory system delivers oxygen and nutrients to cells and takes away wastes.
The heart pumps oxygenated and deoxygenated blood on different sides. The types of blood vessels include arteries, capillaries and veins. Lloyd, M. Give feedback about this page. Was this page helpful? Yes No. View all blood and blood vessels. The carbon dioxide is expelled from the body through the lungs, and the oxygen is taken to the body tissues by the blood. Digestive system. As food is digested, blood flows through the intestinal capillaries and picks up nutrients, such as glucose sugar , vitamins, and minerals.
These nutrients are delivered to the body tissues by the blood. Kidneys and urinary system. Waste materials from the body tissues are filtered out from the blood as it flows through the kidneys.
The waste material then leaves the body in the form of urine. Temperature control. Regulation of the body's temperature is assisted by the flow of blood among the different parts of the body. Heat is produced by the body's tissues as they go through the processes of breaking down nutrients for energy, making new tissue, and giving up waste matter.
A vascular disease is a condition that affects the arteries and veins. Most often, vascular disease affects blood flow, either by blocking or weakening blood vessels, or by damaging the valves that are found in veins. Organs and other body structures may be damaged by vascular disease as a result of decreased or completely blocked blood flow.
Atherosclerosis a buildup of plaque, which is a deposit of fatty substances, cholesterol, cellular waste products, calcium, and fibrin in the inner lining of an artery is the most common cause of vascular disease. It is unknown exactly how atherosclerosis starts or what causes it. Atherosclerosis is a slow, progressive, vascular disease that may start as early as childhood. However, the disease has the potential to progress rapidly.
It is generally characterized by the buildup of fatty deposits along the innermost layer of the arteries. If the disease process progresses, plaque may form. This thickening narrows the arteries and can decrease blood flow or completely block the flow of blood to organs and other body tissues and structures.
Blood clots. A blood vessel may be blocked by an embolus a tiny mass of debris that moves through the bloodstream or a thrombus a blood clot.
In general, inflammation of blood vessels is referred to as vasculitis, which includes a range of disorders. Inflammation may lead to narrowing and blockage of blood vessels. Trauma or injury. Trauma or injury involving the blood vessels may lead to inflammation or infection, which can damage the blood vessels and lead to narrowing and blockage. Because the functions of the blood vessels include supplying all organs and tissues of the body with oxygen and nutrients, removal of waste products, fluid balance, and other functions, conditions that affect the vascular system may affect the part s of the body supplied by a particular vascular network, such as the coronary arteries of the heart.
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