only_in_taxon only in taxon has developmental contribution from has developmental contribution from functionally related to functionally related to composed primarily of mesenchymal cell developmental process Eumetazoa tissue mesoderm mesenchyme Portion of tissue consisting of loosely organized undifferentiated mesodermal cells that give rise to such structures as connective tissues, blood, lymphatics, bone, and cartilage[XAO]. A mesh-like cell arrangement, less compact than an epithelium[ZFA]. The part of the embryonic mesoderm, consisting of loosely packed, unspecialized cells set in a gelatinous ground substance, from which connective tissue, bone, cartilage, and the circulatory and lymphatic systems develop[BTO]. http://upload.wikimedia.org/wikipedia/commons/f/f4/Mesenchymal_Stem_Cell.jpg the relationship to mesoderm is weaker than develops_from in order to have classes such as 'head mesenchyme from mesoderm' make sense AEO:0000145 UBERON:0003104 mesenchymal tissue CALOHA:TS-0620 NCIT:C13301 Portion of tissue composed of mesenchymal cells (motile cells that develop from epthelia via an epithelial to mesenchymal transition) and surrounding extracellular material. Mesenchyme has different embryological origins in different metazoan taxa - in many invertebrates it derives in whole or part from ectoderm. In vertebrates it derives largely from mesoderm, and sometimes the terms are used interchangeably, e.g. lateral plate mesoderm/mesenchyme. AAO:0010427 ZFA:0000393 EV:0100007 portion of mesenchyme tissue uberon VHOG:0000170 EHDAA2:0003145 portion of mesenchymal tissue mesenchyme tissue BTO:0001393 mesenchyma A mesh-like cell arrangement, less compact than an epithelium. Kimmel et al, 1995.[TAO] TAO:0000393 mesenchymal XAO:0003046 Portion of tissue consisting of loosely organized undifferentiated mesodermal cells that give rise to such structures as connective tissues, blood, lymphatics, bone, and cartilage.[AAO] UMLS:C0162415 Wikipedia:Mesenchyme