EntityQ5213758· pop 10· linked from 88 articlesPrimitive knotSign in to saveOrganisational structure around day 17 of vertebrate embryogenesisConnectionsprimitive streakEntitygastrulationEntitycleavageEntityLatinEntitybirdEntityfishEntityAmphibiaEntityInternational Standard Book NumberEntitydigital object identifierEntityInternational Standard Serial NumberEntityembryoEntityzygoteEntityamnioteEntityOCLC, Inc.EntityQ180686EntityHans SpemannEntityNorthwestern UniversityEntityMedical Subject HeadingsEntitygene expressionEntitynotochordEntityCategoriesAnimal developmental biology