The growth cone in neurite extension.
D000818:Animals; D002462:Cell Membrane / Q000502:physiology; D002465:Cell Movement; D002642:Chick Embryo; D002645:Chickens; D008854:Microscopy, Electron; D008928:Mitochondria / Q000502:physiology; D009474:Neurons / Q000166:cytology / Q000254:growth & development / Q000502:physiology*