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Sinus Venarum
The sinus venarum (also known as the sinus of the vena cava, or sinus venarum cavarum) is the portion of the right atrium in the adult human heart where the inner surface of the right atrium is smooth. The sinus venarum represents the portion of the adult heart that develops from the right sinus horn of the foetal sinus venosus. The sinus venarum is demarcated from the rest of the (rough trabeculated) inner surface of the right atrium by the crista terminalis The crista terminalis or terminal crest represents the junction between the sinus venosus and the heart in the developing embryo. In the development of the human heart, the right horn and transverse portion of the sinus venosus ultimately become in .... References {{Portal bar, Anatomy Cardiac anatomy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Right Atrium
The atrium ( la, ātrium, , entry hall) is one of two upper chambers in the heart that receives blood from the circulatory system. The blood in the atria is pumped into the heart ventricles through the atrioventricular valves. There are two atria in the human heart – the left atrium receives blood from the pulmonary circulation, and the right atrium receives blood from the venae cavae of the systemic circulation. During the cardiac cycle the atria receive blood while relaxed in diastole, then contract in systole to move blood to the ventricles. Each atrium is roughly cube-shaped except for an ear-shaped projection called an atrial appendage, sometimes known as an auricle. All animals with a closed circulatory system have at least one atrium. The atrium was formerly called the 'auricle'. That term is still used to describe this chamber in some other animals, such as the ''Mollusca''. They have thicker muscular walls than the atria do. Structure Humans have a four-chambered h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Right Sinus Horn
Rights are legal, social, or ethical principles of freedom or entitlement; that is, rights are the fundamental normative rules about what is allowed of people or owed to people according to some legal system, social convention, or ethical theory. Rights are of essential importance in such disciplines as law and ethics, especially theories of justice and deontology. Rights are fundamental to any civilization and the history of social conflicts is often bound up with attempts both to define and to redefine them. According to the ''Stanford Encyclopedia of Philosophy'', "rights structure the form of governments, the content of laws, and the shape of morality as it is currently perceived". Definitional issues One way to get an idea of the multiple understandings and senses of the term is to consider different ways it is used. Many diverse things are claimed as rights: There are likewise diverse possible ways to categorize rights, such as: There has been considerable debate abou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sinus Venosus
The sinus venosus is a large quadrangular cavity which precedes the atrium on the venous side of the chordate heart. In mammals, it exists distinctly only in the embryonic heart, where it is found between the two venae cavae. However, the sinus venosus persists in the adult. In the adult, it is incorporated into the wall of the right atrium to form a smooth part called the sinus venarum, which is separated from the rest of the atrium by a ridge of fibres called the crista terminalis. The sinus venosus also forms the sinoatrial node and the coronary sinus; in (most) mammals only. In the embryo, the thin walls of the sinus venosus are connected below with the right ventricle, and medially with the left atrium, but are free in the rest of their extent. It receives blood from the vitelline vein, umbilical vein and common cardinal vein. The sinus venosus originally starts as a paired structure but shifts towards associating only with the right atrium as the embryonic heart develops. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crista Terminalis
The crista terminalis or terminal crest represents the junction between the sinus venosus and the heart in the developing embryo. In the development of the human heart, the right horn and transverse portion of the sinus venosus ultimately become incorporated with and forms a part of the adult right atrium, where it is known as the ''sinus venarum''. The line of union between the right atrium and the right atrial appendage is present on the interior of the atrium in the form of a vertical crest, known as the crista terminalis or ''crista terminalis of His''. The crista terminalis is generally a smooth-surfaced, thick portion of heart muscle in a crescent shape at the opening into the right atrial appendage. On the external aspect of the right atrium, corresponding to the crista terminalis is a groove, the terminal sulcus. The crista terminalis provides the origin for the pectinate muscles. See also * Sinoatrial node The sinoatrial node (also known as the sinuatrial node, SA node ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
