Neurenteric canal
In the development of vertebrate animals, during the 6th Carnegie stage, the proximal part of the notochordal canal persists temporarily as the neurenteric canal, which forms a transitory communication between the amniotic sac and the yolk sac cavities. The neurenteric canal is thought to play a role in the maintenance and adjustment of pressure between the amniotic sac and the yolk sac. When the development of the notochord is complete, the neurenteric canal normally closes.
