BlastodermGerm LayersGastrulaEmbryo, NonmammalianBody PatterningGene Expression Regulation, DevelopmentalChick EmbryoEndodermDrosophilaEctodermBlastodiscDrosophila ProteinsEmbryonic InductionMesodermMorphogenesisBlastocystQuailDrosophila melanogasterNodal ProteinPrimitive StreakGerm CellsHomeodomain ProteinsEmbryonic DevelopmentGenes, InsectTriboliumCranial Fossa, PosteriorIn Situ HybridizationOrganizers, EmbryonicBlastulaZebrafishGastrulationInsect ProteinsCoturnixChimeraHeteropteraCell DifferentiationTranscription FactorsPluripotent Stem CellsBlastocyst Inner Cell MassFushi Tarazu Transcription FactorsOtx Transcription FactorsEmbryonic Stem CellsNervous SystemZebrafish ProteinsOctamer Transcription Factor-3Vitelline MembraneEmbryo Culture TechniquesPosterior Cerebral ArteryEmbryo, MammalianInsect HormonesNodal Signaling LigandsGenes, HomeoboxCleavage Stage, OvumNeural PlateCell LineageHeadPosterior Cruciate LigamentMolecular Sequence DataCell MovementGATA6 Transcription FactorFibroblast Growth Factor 4AminopterinMutationBase SequenceDNA-Binding ProteinsNotochordGenes, Lethal