Editing Circulatory system (section)

===Arteries===
{{Main|Aortic arches}}
[[File:Erytrocyte deoxy to oxy v0.7.gif|thumb|Animation of a typical human red blood cell cycle in the circulatory system. This animation occurs at a faster rate (~20 seconds of the average [[Red blood cell#Human|60-second cycle]]) and shows the red blood cell deforming as it enters capillaries, as well as the bars changing color as the cell alternates in states of oxygenation along the circulatory system.]]

The human arterial system originates from the [[aortic arches]] and from the [[dorsal aortae]] starting from week 4 of embryonic life. The first and second aortic arches regress and form only the [[Maxillary artery|maxillary arteries]] and [[Stapedial artery|stapedial arteries]] respectively. The arterial system itself arises from aortic arches 3, 4 and 6 (aortic arch 5 completely regresses).

The dorsal aortae, present on the [[:wikt:dorsal|dorsal]] side of the embryo, are initially present on both sides of the embryo. They later fuse to form the basis for the aorta itself. Approximately thirty smaller arteries branch from this at the back and sides. These branches form the [[intercostal arteries]], arteries of the arms and legs, lumbar arteries and the lateral sacral arteries. Branches to the sides of the aorta will form the definitive [[Renal artery|renal]], [[Inferior suprarenal artery|suprarenal]] and [[Gonadal artery|gonadal arteries]]. Finally, branches at the front of the aorta consist of the [[vitelline arteries]] and [[umbilical arteries]]. The vitelline arteries form the [[Celiac artery|celiac]], [[Superior mesenteric artery|superior]] and [[Inferior mesenteric artery|inferior mesenteric arteries]] of the gastrointestinal tract. After birth, the umbilical arteries will form the [[Internal iliac artery|internal iliac arteries]].