Editing Capillary (section)

== Development ==
During early [[embryonic development]], new capillaries are formed through [[vasculogenesis]], the process of [[blood vessel]] formation that occurs through a novel production of [[endothelial cell]]s that then form vascular tubes.<ref name="Penn2008">{{cite book|author=John S. Penn|title=Retinal and Choroidal Angiogenesis|url= https://books.google.com/books?id=Y-26TIIROYwC&pg=PA119|access-date=26 June 2010|date=11 March 2008|publisher=Springer|isbn=978-1-4020-6779-2|pages=119–}}</ref> The term ''[[angiogenesis]]'' denotes the formation of new capillaries from pre-existing blood vessels and already-present endothelium which divides.<ref name="urlEndoderm -- Developmental Biology -- NCBI Bookshelf">{{cite book |last1=Gilbert |first1=Scott F. |title=Developmental Biology |date=2000 |publisher=Sinauer Associates |location=Sunderland, Mass. |isbn=0-87893-243-7 |edition=6th |chapter=Endoderm |url=https://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=dbio&part=A3745 |access-date=1 February 2021}}</ref> The small capillaries lengthen and interconnect to establish a network of vessels, a primitive vascular network that vascularises the entire [[yolk sac]], [[connecting stalk]], and [[chorionic villi]].<ref name="Larsen">{{cite book |last1=Schoenwolf |first1=Gary C. |title=Larsen's human embryology |date=2015 |location=Philadelphia, PA |isbn=9781455706846 |page=306 |edition=Fifth}}</ref>