Notochorde
The notochorde is a cartilagineuse structure rigid, but flexible, located dorsalement. It represents one of the five characteristics specific to the Chordés. It lengthens over the length of the body and thus consists of an axis for the attachment of the muscles.
Protochordés
At the group of the Protochordés, the notochorde is present at least at a stage of the life. This group includes/understands two subphyla: the Urochordés and the Céphalochordés.
Urochordés
At the subphylum of the Urochordés, or tunicates, the notochorde is present in the larva. On the other hand, after a metamorphosis which transforms the larva into adult, the majority of time Sessile, the notochorde disappears. Indeed, the larva of Protochordés has the five characteristics of the Chordés, but the adult loses, in addition to the notochorde, the post-anal tail and the dorsal Tube neural which is him reduces to a simple ganglion.
Céphalochordés
At the subphylum of the Céphalocordés, or amphioxus, the various species preserve the five characteristics of the Chordés throughout their life, of which the notochorde.
Vertebrate
This subphylum is sometimes gathered in the groups of the Crâniates or is indicated alternatively by this same name. At the Vertebrate , the notochorde is present at the embryo. It persists at the Agnathes and disappears in the adult from the Gnathostomes.
Embryology of the Vertebrate ones
Human embryology
Sources
| Random links: | Fibroblast | Sidney Poitier | Dino Meneghin | Canton of Monségur | Coed trade union federation unit and laic |