part_of part of part of dorsal to dorsal_to ventral to ventral_to only_in_taxon only in taxon develops_from develops from develops from existence starts during produces produces Chordata sonic hedgehog protein organ embryo stage multi-tissue structure neural tube digestive tract notochord MESH:A16.254.610 http://upload.wikimedia.org/wikipedia/commons/6/64/Gray19_with_color.png notochorda AAO:0000327 uberon (...) at some stage of its development, every chordate exhibits five uniquely derived characters or synapomorphies of the group: (...) (3) a stiff, longitudinal rod of turgid cells along the dorsal part of the body that is called a notochord (...).[well established][VHOG] XAO:0000055 VHOG:0000199 FMA:85521 NCIT:C12463 In between vertebra the notochord becomes the nucleus pulposus, under it degenerates, and at anterior end in some species its tissue merges with some of the cranial bones.. Some organisms retain a post-embryonic notochord. VSAO:0000032 CALOHA:TS-0690 The notochord appears early in embryogeny and plays an important role in promoting or organizing the embryonic development of nearby structures. In most adult chordates the notochord disappears or becomes highly modified. In some non-vertebrate chordates and fishes the notochord persists as a laterally flexible but incompressible skeletal rod that prevents telescopic collapse of the body during swimming[TOLWEB] UMLS:C0028439 EHDAA:6021 notochordal http://evolution.berkeley.edu/evolibrary/images/history/notochords.jpg A flexible rod-shaped body found in embryos of all chordates. It is composed of cells derived from the mesoderm and defines the primitive axis of the embryo. In some chordates, it persists throughout life as the main axial support of the body, while in most vertebrates it becomes the nucleus pulposus of the intervertebral disc. The notochord is found ventral to the neural tube. MESH:D009672 Avascular multi-tissue structure composed of large vacuolated epithelial cells (chordablasts) and perichordal fibrous tissue.[VSAO] Rod-like principal supportive element of the embryo and larva, present in the midline just ventral to the neural tube, and differentiating during the segmentation period to form large vacuolated epithelial cells and a surrounding a sheath of fibrous and elastic layers. Layering of the sheath may differ in structure, thickness and development among groups; in cypriniforms there are actually three very thin layers to the sheath. A functional, well developed notochord is present throughout life in certain basal fish groups but not in cypriniforms. Kimmel et al, 1995.[TAO] UBERON:0002328 GAID:1311 EMAPA:16191 EHDAA:1241 Wikipedia:Notochord BTO:0001768 SCTID:308820002 embryonic notocord EHDAA2:0001277 notocord ZFA:0000135 EV:0100002 relationship type change: differentiates_from mesoderm (AAO:0000304) CHANGED TO: develops_from mesoderm (UBERON:0000926)[AAO] TAO:0000135 Slender rod of fibrous connective tissue surrounding a core of fluid-filled cells of mesodermal origin; it lies above the gut and directly beneath the spinal cord. The notochord is present during early development and in a few cases it is retained through life; however, usually the notochord is replaced by the vertebral column.[AAO] MAT:0000281 mesoderm-derived structure ectoderm-derived structure chordamesoderm notochordal plate axial skeletal system