Day22-cell stageDay34-cellstageDay4MorulaActualembryoDay5Day1BlastocystFirstcleavageFeedingcellsDayOCorpusFertilizationluteumDay6BlastocystattachesOvaryampullaDay7SpermEmplantingembryohCGOvum(12-24h)OviductEstrogenandDay10OvulationprogesteroneImplantedembryoMaintains uterine liningChorionfrom10daysuntilendofsecondmonthUterinelining(a)
ampulla (12-24h)
4.Bilaminar Germ DiscAmnioticcavitysyncytiotrophoblastEpiblastExtra-embryonicPrimitivemesodermyolk sacHypoblastEmbryonicDisk
Extraembryonic mesoderm Embryonic Disk 4. Bilaminar Germ Disc Hypoblast Amniotic cavity Epiblast Primitive yolk sac syncytiotrophoblast
FormationofAmnioniccavityandYolkSacAmnioniccavitySplanchnicoSomaticCREEORDcb000800Embryonic990000disk.aExtraembryonicExtraembryoniccavitymesodermoo006c..odooao.0eB00DPrimaryvillus5.cccoaocc.oo.ooo...ooo.amYolk sacFunction: protection and nutrition
Formation of Amnionic cavity and Yolk Sac Function: protection and nutrition Amnionic cavity Yolk sac Extraembryonic mesoderm Embryonic disk Extraembryonic cavity Primary villus Splanchnic Somatic
Formationof extraembryoniccavity&BodyStalkVilliBody StalkeASplanchnicExtraembryonicmesodermSomaticExtraembryoniccavityBody stalk: the connection structure between thedisk/amnionic cavityandtrophoblastsUmbilicalCord
Formation of extraembryonic cavity & Body Stalk Body stalk：the connection structure between the disk/amnionic cavity and trophoblasts. Body Stalk Extraembryonic mesoderm Splanchnic Extraembryonic cavity Somatic Villi Umbilical Cord
合体滋养层细胞滋养层波养层陷窝血管AreaofprochordalplateCut edgeofamnionepiblasthypoblastWallofyolksac初级卵Primitive0黄素streakEpiblastHypoblast胚体体腔膜凝栓Period oftwos:EpiblastEmbryoincDisk2flat germ layersHypoblast2trophoblastlayers?When:by the 2nd week2cavities
Epiblast Hypoblast Embryoinc Disk ? When： by the 2nd week Period of twos: 2 flat germ layers 2 trophoblast layers 2 cavities epiblast hypoblast