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Anatomy: Embryology Mid‑importance This article is within the scope of WikiProject Anatomy, a collaborative effort to improve the coverage of Anatomy on Wikipedia. If you would like to participate, please visit the project page, where you can join the discussion and see a list of open tasks.AnatomyWikipedia:WikiProject AnatomyTemplate:WikiProject AnatomyAnatomy articles Mid This article has been rated as Mid-importance on the project's importance scale. This article has been classified as relating to embryology.

I merged the Extra-embryonic coelom article to here, because in practice the gestational sac is only relevant during embryogenesis, during which the volume almost entirely consists of the extra-embryonic coelom. I've explained in the intro that the volume is later replaced by the amniotic sac, and by that time it is usually called by that name instead. Mikael Häggström ( talk) 09:08, 12 July 2014 (UTC) reply