part_of part of part of has part has part has_part develops_from develops from anatomical entity anatomical entity trophectodermal cell morula unilaminar epithelium trophectoderm VHOG:0000979 distinction between trophectoderm and trophoblast unclear/inconsistent in many sources BTO:0001840 The outer cellular layer of the mammalian blastocyst. [Evolution, Fourth_Edition_(2006)_McGraw-Hill, Function, Vertebrates:_Comparative_Anatomy, p.750, see_Kardong_KV][VHOG] trophectodermal Outermost layer of cells in the blastodermic vesicle, which will develop into the trophoblast layer and then contact the endometrium and take part in establishing the embryo's means of nutrition. uberon UBERON:0004345 BTO has this has part of the trophoblast EHDAA:56 (...) the trophoblast develops rapidly so that contact may be made with the maternal uterine tissues when conditions are appropriate. We have here an excellent example of an embryonic adaptation, the development of a structure never present in either adult or embryo of 'lower' vertebrates.[well established][VHOG] EHDAA2:0002091 EMAPA:16046 extraembryonic tissue extraembryonic membrane