大连医科大学：《组织胚胎学》课程教学课件（英文讲稿）G2-embryology

Day22-cell stageDay34-cellstageDay4MorulaActualembryoDay5Day1BlastocystFirstcleavageFeedingcellsDayOCorpusFertilizationluteumDay6BlastocystattachesOvaryampullaDay7SpermEmplantingembryohCGOvum(12-24h)OviductEstrogenandDay10OvulationprogesteroneImplantedembryoMaintains uterine liningChorionfrom10daysuntilendofsecondmonthUterinelining(a)

ampulla (12-24h)

4.Bilaminar Germ DiscAmnioticcavitysyncytiotrophoblastEpiblastExtra-embryonicPrimitivemesodermyolk sacHypoblastEmbryonicDisk

Extra￾embryonic 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

SummarySperm FertilizationCleavageZygoteMorulaOvumAmnioniccavityEndometrium(2 W)Ecto+-EpiblastEmbryonicICMBlastocystDiskimplantationEndo---hypoblastCavityYolksacCyto-BasalisTrophoblastCapsularisDecidualSynParietalisSomatopleureExtra-SplanchnopleureEmbryonicmesodermBodystalk

Sperm Ovum Zygote Morula Blastocyst Endometrium Fertilization Cleavage Trophoblast Cavity ICM Decidual Basalis Capsularis Parietalis Embryonic Disk （2 W） Cyto￾Syn￾Extra￾Embryonic mesoderm Splanchnopleure Somatopleure Body stalk Amnionic cavity Yolk sac Endo-hypoblast Ecto- Epiblast implantation Summary

5.Trilaminar Germ layers (week3)Formation of primitive streak4561.Primitivestreak023Rostral2.PrimitivenodeaU9epiblastic cells-primitive streak(primitivegroove,primitivenode)

5. Trilaminar Germ layers (Week 3 )  Formation of primitive streak epiblastic cells →primitive streak (primitive groove, primitive node ) 1. Primitive streak 2. Primitive node

Cut edgeofamnionYolk sacPrimitiveEpiblaststreakAmnionCutB-YolkAInvaginatingHypoblastsacPrimitivemesodermcellsPrimitivenodestreakSignificance: 1) determine the middle axis ;2) determine cranial-caudal-axis;3) Induce mesoderm

Significance: 1) determine the middle axis ; 2) determine cranial-caudal-axis; 3) Induce mesoderm Cut

PrimitivenodePrimitivestreakAmniotic cavityEpiblastYolkSacDevelopingHypoblastmesodermalcells? When: By the end of the 3rd Week?What:Formation of the trilaminargermlayers(allfromepiblast)

? When: By the end of the 3rd Week, ?What: Formation of the trilaminar germ layers Epiblast Primitive node Primitive streak Yolk Sac Developing Hypoblast mesodermal cells Amniotic cavity (all from epiblast)

FormationofNotochordCranialcauPrimitivenodeCaudalEpiblastcells-→primitivenode-→notochordal (head)process

Epiblast cells → primitive node → notochordal (head) process  Formation of Notochord Primitive node Cranial Caudal