This is the remnant of the Botal duct (Latin ductus arteriosus (Botalli)), through which the fetus and blood entering the right ventricle are redirected from the pulmonary artery to the aorta: a small circle in the fetal stage of development does not function. In the future, the duct is obliterated (parallel overgrowth of the oval hole in the atrial septum).
Artery
An artery is a blood vessel that carries blood away from the heart to other parts of the body. Almost all arteries carry blood with a lot of oxygen in it. The only arteries that do not carry oxygen-rich blood are the pulmonary artery, and (in a fetus) the umbilical artery.
Every artery has three layers. The outer layer is a thick covering made of stretchy tissue. The middle layer is made of muscle, so the artery can get wider or get smaller when the body needs it to. The inner lining is made of the same cells that line the heart.
Arteries are deep under the skin. They do not have valves to prevent blood from flowing backwards. Instead, every time the heart beats, the arteries stretch out so the blood has room to go through. Once the walls have completely stretched out, the muscles in the arteries make them shrink back to their normal size. This pushes the blood through.
Arteries split down into small vessels called "arterioles".
The aorta is the main artery in the human body. It starts in the left ventricle of the heart, which is full of blood that just picked up oxygen in the lungs. (This is called "oxygenated" blood - meaning it has a lot of oxygen in it.) The left ventricle pumps this oxygen-rich blood out through the aorta. The aorta brings this blood to every organ in the body.
The aorta runs all the way from the heart to the bottom of the abdomen. Along the way, smaller arteries split off the aorta, like branches on a tree, to bring blood to different parts of the body. The aorta finally ends by splitting off into the two arteries that bring blood to the legs.
Except for the pulmonary artery, every artery in the body is connected to the aorta. Some other important arteries include:
The pulmonary artery is the only artery in the adult body that:
The body uses the oxygen carried in the other arteries to make energy. The blood in these arteries becomes "deoxygenated" - it does not have much oxygen left in it. This blood then travels through capillaries to get from the arteries to the veins. The veins' job is to carry the "deoxygenated" blood back to the right side of the heart. The pulmonary artery carries this blood from the heart's right ventricle to the lungs. In the lungs, the blood can pick up more oxygen.
After picking up more oxygen, the blood travels back to the left side of the heart and is pumped out to the body by the aorta. This cycle continues, over and over again.
Because the heart pumps blood right into the arteries, the arteries are under a lot of pressure. Unlike the veins, the arteries are always stretching and then squeezing to push blood through them to the body. Because of this, an "arterial bleed" - bleeding from an artery - can be a medical emergency, especially if the artery is big. Arterial bleeding can happen very quickly. For example, if a person's femoral artery is cut, they can bleed to death.
If an artery in the brain starts bleeding, the bleeding can cause a stroke.
When a person has arteriosclerosis, the walls of their arteries get harder, stiffer, and less stretchy. This makes it more difficult for blood and oxygen to get through the arteries to the body's important organs.
One type of arteriosclerosis is atherosclerosis. Atherosclerosis is a disease where the arteries get narrower because they are clogged up with things like cholesterol and fat. Like a clog in sink pipes makes it harder for water to get through the pipes, clogs in arteries make it more difficult for blood to get through. This makes the heart have to work harder to push blood through the arteries. Atherosclerosis is a big risk factor for high blood pressure and heart disease.
When atherosclerosis happens in the coronary arteries, it can cause coronary heart disease. If these arteries get too clogged, the heart will not get the blood and oxygen it needs to survive. This can cause angina, a heart attack, heart failure, or even sudden death.
When atherosclerosis happens in one of the arteries in the brain, it can cause a stroke.
An aneurysm is a bulge in the wall of an artery. It is like a little balloon, filled with blood, coming off the artery. As the aneurysm gets bigger, it is more likely to break. If the aneurysm breaks ("ruptures"), the artery will start bleeding. If the artery is big, a person could bleed to death. Also, if an artery is bleeding, blood cannot get through it. The part of the body that the artery is supposed to feed will not get the blood and oxygen it needs. A ruptured aneurysm is a medical emergency.
Jönköping
Jönköping is a city in Sweden. About 90,000 people live there. It is in southern Sweden near the lake Vättern.
Jönköping was actually 3 towns that grew into one large town. The 3 towns were, "Jönköping (55.000)", "Huskvarna (22.000)" and "Norrahammar (9.000)".
Jönköping is the 9th biggest city in Sweden.
Warwickshire
Warwickshire (pronounced //, //, or //) is a county in central England. The county town is Warwick. The shape of the administrative area Warwickshire differs considerably from that of the historic county. Commonly used abbreviations for the county are Warks or Warwicks.
Warwickshire is perhaps best known for being the birthplace of William Shakespeare from Stratford-upon-Avon. The county has also produced other literary figures such as George Eliot (from near Nuneaton), Rupert Brooke (from Rugby), and Michael Drayton from Hartshill.
Warwickshire is bounded to the northwest by the West Midlands metropolitan county, and Staffordshire, by Leicestershire to the northeast, Northamptonshire to the east, Worcestershire to the west, Oxfordshire to the south, Gloucestershire to the southwest.
The majority of Warwickshire's population live in the north and centre of the county. The market towns of northern and eastern Warwickshire were industrialised in the 19th century, and include Atherstone, Bedworth, Nuneaton, and Rugby. Major industries included coal mining, textiles, engineering, and cement production, but heavy industry is in decline. Of the northern and eastern towns, only Nuneaton and Rugby (as the birthplace of Rugby football) are well-known outside of Warwickshire. The rich towns of central and western Warwickshire include Leamington Spa, Stratford-upon-Avon, Kenilworth, Alcester, and Warwick. They have light to medium industries, services, and tourism as major employers.
The south of the county is largely rural and has little population, and includes a small area of the Cotswolds. The only town in the south of Warwickshire is Shipston-on-Stour. The highest point in the county, at 261 m (856 ft), is Ebrington Hill on the border with Gloucestershire, GR SP187426 at its southwest extremity.
There are no cities in Warwickshire since both Coventry and Birmingham were incorporated into the West Midlands county in 1974. The largest towns in Warwickshire as of 2004 are: Nuneaton (pop. 77,500), Rugby (62,700), Leamington Spa (45,300), and Bedworth (32,500). Stratford, Warwick, and Kenilworth all house populations with more than 20,000 inhabitants, the smaller towns of Atherstone, Alcester, Coleshill, Southam, Bulkington, Polesworth, Kingsbury, Henley-in-Arden, Studley, Shipston and Whitnash have populations between 5,000 and 12,000.
Historically much of western Warwickshire, was covered by the ancient Forest of Arden (although most of this was cut down to provide fuel for industrialisation in the 17th to 19th centuries). For this reason, the names of a number of places in the northwestern part of Warwickshire end with the phrase "-in-Arden".