A midline cellular cord formed from the migration of mesenchymal cells from the primitive knot. [ http://www.med.umich.edu/lrc/coursepages/m1/embryology/embryo/05embryonicperiod.htm ]
Term information
- VHOG:0001213
- EHDAA2:0001279
- NCIT:C34232
- UMLS:C1518430 (ncithesaurus:Notochordal_Process)
- FMA:293135
- EHDAA:224
- EMAPA:16102
emapa_ehdaa2
The notochordal process grows cranially until it reaches the prechordal plate, the future site of the mouth. In this area the ectoderm is attached directly to the endoderm without intervening mesoderm. This area is known as the oropharyngeal membrane, and it will break down to become the mouth. At the other end of the primitive streak the ectoderm is also fused directly to the endoderm; this is known as the cloacal membrane (proctodeum), or primordial anus.