Вы можете отметить интересные вам фрагменты текста, которые будут доступны по уникальной ссылке в адресной строке браузера.

Atrium (heart)

Atrium (heart)

In anatomy, the atrium "(plural: atria)" refers to a chamber or space. It may be the atrium of the lateral ventricle in the brain or the blood collection chamber of a heart. It has a thin-walled structure that allows blood to return to the heart. There is at least one atrium in animals with a closed circulatory system. In fish, the circulatory system is very simple: a two-chambered heart including one atrium and one ventricle. In other vertebrate groups, the circulatory system is much more complicated. Their circulatory systems are divided into two types: a three-chambered heart, with two atria and one ventricle, or a four-chambered heart, with two atria and two ventricles. The atrium receives blood as it returns to the heart to complete a circulating cycle, whereas the ventricle pumps blood out of the heart to start a new cycle.

Human heart

Humans have a four-chambered heart. The right atrium receives de-oxygenated blood from the superior vena cava, inferior vena cava and coronary sinus. The left atrium receives oxygenated blood from the left and right pulmonary veins. The atria do not have valves at their inlets. As a result, a venous pulsation is normal and can be detected in the jugular vein.

Internally, there is the rough musculae pectinati and crista terminalis, which acts as a boundary inside the atrium and the smooth walled part derived from the sinus venosus. There is also a fossa ovalis in the interatrial septum which is used in the fetal period as a means of bypassing the lung.

There are two atria, one on either side of the heart. On the right side is the atrium that holds blood that needs oxygen. It sends blood to the right ventricle which sends it to the lungs for oxygen. After it comes back, it is sent to the left atrium. The blood is pumped from the left atrium and sent to the left ventricle where it is sent to the aorta which takes it to the rest of the body. Yo momma is a ventricle!!! But not for free.

See also

* Atrial syncytium
* Atrial fibrillation


Wikimedia Foundation. 2010.

  
Share  

Look at other dictionaries:

  • Heart chamber — is a general term used to refer to any chambers of the mammalian heart. The heart consists of four chambers: the right and left atrium and the right and left ventricle. The top chambers are connected to the bottom chambers by valves and are… …   Wikipedia

  • Heart failure — Classification and external resources The major signs and symptoms of heart failure. ICD 10 I5 …   Wikipedia

  • Heart transplantation — or cardiac transplantation, is a surgical transplant procedure performed on patients with end stage heart failure or severe coronary artery disease. The most common procedure is to take a working heart from a recently deceased organ donor… …   Wikipedia

  • Atrium — may refer to: *Atrium (architecture), a large open space within a building *Atrium (heart), an anatomical structure of the heart *Atrium (Cardiff), a University of Glamorgan (Wales) building in Cardiff *Atrium (band), A screamo band based in York …   Wikipedia

  • Heart valve repair — Intervention ICD 9 CM 35.0 35.2 Heart valve repair is a surgical technique used to fix defects in …   Wikipedia

  • Atrium — A tri*um, n.; pl. {Atria}. [L., the fore court of a Roman house.] 1. (Arch.) (a) A square hall lighted from above, into which rooms open at one or more levels. (b) An open court with a porch or gallery around three or more sides; especially at… …   The Collaborative International Dictionary of English

  • Atrium By Bridgestreet (Manchester) — Atrium By Bridgestreet country: United Kingdom, city: Manchester (City) Atrium By Bridgestreet Location Situated in the heart of Manchester, at the junction of Princess Street and Whitworth Street, The Atrium by Bridgestreet boasts stylish… …   International hotels

  • heart — /hahrt/, n. 1. Anat. a hollow, pumplike organ of blood circulation, composed mainly of rhythmically contractile smooth muscle, located in the chest between the lungs and slightly to the left and consisting of four chambers: a right atrium that… …   Universalium

  • Heart — This article is about the organ in various animals. For the human heart, see Human heart. For other uses, see Heart (disambiguation). Cardiac redirects here. For the cardboard computer, see CARDboard Illustrative Aid to Computation …   Wikipedia

  • atrium — atrial, adj. /ay tree euhm/, n., pl. atria /ay tree euh/, atriums. 1. Archit. a. Also called cavaedium. the main or central room of an ancient Roman house, open to the sky at the center and usually having a pool for the collection of rain water.… …   Universalium