Development of Venous System Flashcards
(31 cards)
What are the 3 pairs of veins that each of the right and left sinus horns receives blood
from?
vitelline (omphalomesenteric) veins, umbilical veins, common cardial veins
The _____ divides the embryonic cavity into thorax and abdominal cavities
septum transversum
What do the vitelline veins (1st veins formed) arise from?
capillary plexus of the yolk sac
What is the extensive vascular network that forms partially from the vitelline veins?
hepatic sinusoids
Which side are most venous structures on?
Right b/c RA must receive venous blood
We start with paired vitteline veins. But one disappears – which one?
Left one disappears, so blood is channeled to the right vitelline vein creating the right
hepatocardiac channel
What does the right vitelline vein (hepatocardiac channel) become?
Terminal portion of the IVC
What does the portal system drain?
blood from the GI tract to the hepatic sinusoids
What are all the major derivatives of the vitelline veins?
hepatic sinusoids, the portal vein and superior mesenteric vein, the terminal IVC
What do the vitelline or omphalomesenteric veins do?
Carry blood from the yolk sac to the sinus venosus
What do the umbilical veins do and where do they originate?
Carry oxygenated blood from the placenta to the sinus venosus; originate in the
chorionic villi
What do the cardinal veins do?
Carry blood from the body of the embryo to the sinus venosus
Which umbilical vein disappears?
The RIGHT vein disappears. The left umbilical vein carries OXYGENATED blood
from the placenta to the liver
What do the left umbilical and right vitelline veins do?
left umbilical vein delivers blood to the “liver” and the right vitelline vein (portal
system) delivers blood to the “liver” as well
What are the derivatives of the umbilical veins?
No derivatives, one remnant: ligamentum teres hepatis (edge of falciform ligament)
Which cardinal veins drain the superior embryo?
Anterior cardinal veins (AS-IP acronym)
Which does the posterior cardinal vein drain?
Inferior embryo (rest of body=caudal) (AS-IP acronym)
The distal portion of the anterior cardinal veins become what
Internal jugular veins
When the left anterior cardinal vein obliterates, what is the remnant?
Coronary sinus
What does the anastomosis between the anterior cardinal veins become
Left brachiocephalic vein
The proximal right anterior and right common cardinal veins become the
SVC
Which two sets of veins are created as the embryo needs more circulation during the 5th-
7th weeks of development? These replace the posterior cardinal veins
supracardinal veins (body wall), subcardinal veins (kidneys and gonads)
Blood from the intercostal veins (think somites) drain into the
supracardinal veins
What is the advantage of the presence of the azygous vein?
blood can “bypass” the IVC. If the vena cava is occluded, blood can return to the heart
via the azygous systems – alternate drainage of the body to the heart
