Name: | maxilla |
---|---|
Synonyms: | maxillae |
Definition: | The dermal maxilla forms part of the upper jaw. It is first visible as a small dorsoventrally oriented rod of bone in the lateral region of the upper jaw. Through anterior ossification it becomes S-shaped, with its anteriormost tip directed medially (4.8 mm NL). The posteroventral end of the maxilla is connected to the dentary by a ligament. Maxillary teeth are absent in cypriniforms, but are present in other ostariophysans. Two barbels are present on the maxilla. The presence of two pairs of maxillary barbels is considered by Cavender and Coburn (1992) to be the primitive condition for the Cyprinidae. |
Ontology: | Anatomy Ontology [ZFA:0000270] |
Name: | neural crest cell |
---|---|
Synonyms: | neural crest cells |
Definition: | A cell of the neural crest. The neural crest is a strip of specialized ectoderm, the neural plate border, which flanks each side of the embryonic neural plate. Neural crest cells are multipotent. Premigratory neural crest cells are found at the neural plate boarder, some of which will undergo ectomesenchymal transition and delamination to form migratory neural crest cells. Most of the cranial and all of the spinal sensory ganglion cells arise by differentiation of neural crest cells. |
Ontology: | Anatomy Ontology [ZFA:0009165] |