Fetal membranes, Placenta and Twinning Eow Or 3-eed-cad Jun zhou(周俊) School of medicine, ZheJiang University 20190611
Fetal Membranes, Placenta and Twinning Jun Zhou (周俊） School of Medicine, ZheJiang University 20190611
OBJECTIVES 1. The components of fetal membrane and their functions 2. Structure and function of placenta 3. Composition of Placenta barrier
OBJECTIVES 1. The components of fetal membrane and their functions. 2. Structure and function of placenta 3. Composition of Placenta barrier
Fetal membrane(胎膜) o Originate from blastocyst (i 多“ /Amnion sE), don' t participate in the Embryo yOlk sac formation of embryo Charion iNcluding 1) Chorion(绒毛膜) 2) Amnion(羊膜) 3) Yolk sac(卵黄囊) 4) allantois(尿囊) 5)儿 mbilical cord(脐带) Extraembryonic Membranes
Fetal membrane （胎膜） •Originate from blastocyst（胚 泡）, don’t participate in the formation of embryo •Including: 1) Chorion（绒毛膜） 2) Amnion（羊膜） 3) Yolk sac（卵黄囊） 4) Allantois（尿囊） 5)Umbilical cord（脐带）
Chorion(绒毛膜) Formed by trophoblast +extraembryonic mesoderm chorion frondosum(丛密绒毛膜) embryonic pole Chorion laeve(平滑绒毛膜) abembryonic pole Decidua basalis Decidua Chorion parietalis frondosum connecting Chorion cavity. Decidua capsularIs Uterine
Chorion（绒毛膜） •Formed by trophoblast +extraembryonic mesoderm •Chorion frondosum（丛密绒毛膜）- embryonic pole •Chorion laeve（平滑绒毛膜）- abembryonic pole
Chorion Primary villi(2w): cytotrophoblast +-syncytiotrophoblast Secondary villi (3w): extraembryonic mesoderm enter the primaryⅷii Tertiary villi (end of 3w ) extraembryonic mesoderm cT+BV y 复 6细血置 connecting y 胞战春层壳 chorionic yncytiotrophobla @ A Primary B C Tertiary villus
Chorion • Primary villi (2w): cytotrophoblast+syncytiotrophoblast • Secondary villi (3w):extraembryonic mesoderm enter the primary villi • Tertiary villi (end of 3w): extraembryonic mesoderm =>CT+BV
Function of chorion 1)Exchange of metabolite portion of placenta( chorion frondosum) 2)Hormone production human chorionic gonadotropin绒毛膜促性腺激素 (HCG
Function of Chorion 1) Exchange of metabolite: portion of placenta (Chorion frondosum) 2) Hormone production: human chorionic gonadotropin绒毛膜促性腺激素 (HCG)
Amnion(羊膜) .Amniotic membrane: amniotic epi. extraembryonic mesoderm ● Amniotic fluid: Produce: 1 )amniotic cells 2)urine output from the fetus Output: 1)absorbed by amniotic cells 2)fetus swallow 1-1.5 liter -circulate
Amnion（羊膜） •Amniotic membrane: amniotic epi.+ extraembryonic mesoderm •Amniotic fluid: Produce:1)amniotic cells 2) urine output from the fetus Output: 1) absorbed by amniotic cells 2) fetus swallow •1-1.5 liter – circulate
Amnion- Fluid Intervales no Vious thorn wol tar ● Functions Mechanically cushion M比o Protect from fetus adhesion Decidua te Movement Uterine cavily Maintain Temp Amnon tumon choon) Degenerating dect capsularis Mucous plug
Amnion - Fluid • Functions – Mechanically cushion – Protect from fetus adhesion – Movement – Maintain Temp
Abnormalities 1)too much (polyhydramnios >1500ml Abnormal digestive system or CNS esophageal atresia(食管闭锁) anencephaly(无脑儿) 2)too little(oligohydramnios) <500m Abnormal urinary system poor development of kidney(肾脏发育不全) urethra atresia(尿道闭锁)
• Abnormalities 1) too much (polyhydramnios) >1500 ml Abnormal digestive system or CNS - esophageal atresia(食管闭锁） - anencephaly（无脑儿） 2) too little (oligohydramnios) <500 ml Abnormal urinary system - poor development of kidney（肾脏发育不全） - urethra atresia（尿道闭锁）
Yolk sac and allantois · Yolk sac(卵黄囊) Respiratory Primitive gut Heart Liver bud 3rd week, Germ Cells Duodenum duct 3rd to 6th week Allantois-fE Blood island Hindgut 地Gog吨w Al| antos(尿囊) The placenta and the Umbilical cord Caudal extension of hindgut Uterus Allantoic A pairs Umbilical cord Bood Umbilical Allantoic V pairs arteries Connecting Umbilical cord Umbilical chorion Umbilical vessels veIn Placenta Fetal portion Maternal of placenta portion of 2A+1V placenta
Yolk sac and Allantois • Yolk sac（卵黄囊） – Primitive Gut – 3 rd week, Germ Cells – 3 rd to 6th week, Blood island • Allantois（尿囊） – Caudal extension of hindgut – Allantoic A pairs – Allantoic V pairs Umbilical vessels 2A+1V
