1) Bodily cavity 2) Cavity 3) Cavum 1) Primitive gut 2) Protogaster 
The primitive gut that forms during gastrulation in the developing embryo is known as the archenteron or the digestive tube. It develops into the digestive tract of an animal. ==Formation of the Archenteron in Sea Urchins== As primary mesenchyme cells detach from the vegetal pole in the gastrula and enter the fluid filled cavity in the center (the...
• (n.) The primitive enteron or undifferentiated digestive sac of a gastrula or other embryo. See Illust. under Invagination.
(from the article `digestive system, human`) ...embryo converts the initially single-layered embryo into a two-layered one, a process called gastrulation. The new inner layer of cells, called ... ...on the exterior become the ectoderm. As a consequence of the infolding at the vegetal pole, the blastocoel is reduced or obliterated, and a...
(ahrk-en´tәr-on) the central cavity that is the provisional gut in the gastrula; the primordial digestive cavity of the embryo.
Arch`en'ter·on noun [ Prefix arch- + Greek ... intestine.] (Biol.) The primitive enteron or undifferentiated digestive sac of a gastrula or other embryo. See Illust. under Invagination . 
Type: Term Pronunciation: ark-en′ter-on Synonyms: primordial gut
The primitive digestive tract of the embryo that will develop into the intestinal or digestive cavity.
[n] - central cavity of the gastrula
archenteron The central cavity of the gastrula, which ultimately becomes the intestinal or digestive cavity.
noun central cavity of the gastrula; becomes the intestinal or digestive cavity
the primitive enteron or digestive cavity of a gastrula.