《组织学与胚胎学 Histology and Embryology》课程PPT教学课件讲稿（英文版）Chapter 21 General Embryology

Chapter 21 General Embryology

Chapter 21 General Embryology

a science which study the processes and regulations of development of human fetus.(from 1 cell(zygote)to (5-7)X1012 cells total 38 weeks preembryonic period: before 2 weeks

---a science which study the processes and regulations of development of human fetus.(from 1 cell(zygote) to (5-7)X1012 cells ) ---total 38 weeks: preembryonic period: before 2 weeks

embryonic period 3-8 weeks 3周 4周 5周 6周 7周 8周 fetal period: after 9 weeks perinatal stage: 26 weeks to birth 9周16周 36)(38周 Teratology: abnormal development of fetus

embryonic period: 3-8 weeks fetal period: after 9 weeks *perinatal stage: 26 weeks to birth *Teratology: abnormal development of fetus

fErtilization definition the process by Which the male and female gametes(sperm and ovum) unite to give rise to zygote ---place: in the ampullary region of the fallopian tube

1.Fertilization ---definition: the process by which the male and female gametes(sperm and ovum) unite to give rise to zygote ---place: in the ampullary region of the fallopian tube

精原细胞 娴细所 初级精母 细形6,XY)○ 初级卵母细胞 次级精 时细肥 精子 细胞 次级卵母 极体 23.x23,Y23,x123Y 细23 精子 极体 卵f conditions 1) maturation of oocyte 2) maturation of spermatozoon /ductus epididymus: 2-3 weeks, forward motility protein

---conditions: 1) maturation of oocyte 2) maturation of spermatozoon: /ductus epididymus: 2-3 weeks, forward motility protein

3)capacitation of spermatozoa o decapacitation factor: exist in epididymus, to inhibit the release of acrosome enzvmes e capacitation factor: secreted by epi cells of oviduct, capacity of releasing acrosome enzvmes

3) capacitation of spermatozoa: decapacitation factor: exist in epididymus, to inhibit the release of acrosome enzymes capacitation factor: secreted by epi. cells of oviduct, capacity of releasing acrosome enzymes

4)quality and quantity of spermatozoa 2-6ml,100.000.000/ml 30%,or/capacity for mobile< 70 5)meeting of sperm and ovum ● sperm:20-24h ●ovum:15-18h(1-3ds)

4) quality and quantity of spermatozoa: 2-6 ml, 100,000,000/ml, 30%; or capacity for mobile< 70% 5) meeting of sperm and ovum sperm: 20-24h ovum: 15-18h(1-3ds)

获能后 透明带 processes of fertilization 一穿入后的精子尾 acrosome reaction 子头部 /hyaluronic acidase: dissolve corona radiate interact with ZP3(receptor glycoprotein, exist in zona pellucid) molecules, release acrosin dissolve zona pellucid enter perivitelline space

---processes of fertilization: 1) acrosome reaction: /hyaluronic acidase: dissolve corona radiate * interact with ZP3(receptor glycoprotein, exist in zona pellucide) molecules, release /acrosin: dissolve zona pellucide /enter perivitelline space

2)spermatozoa fuse with the membrane of ovum: nucleus enter cytoplasm of ovum 3)monospermy cortical reaction: cortical granules(located in cytoplasm of ovum)/are released into perivitelline space, and cause zona reaction: change of ZP3 molecules in zona pellucid 4) formation of zygote(fertilized ovum secondary meiosis complete: form second polar body male pronucleus fuse with female pronucleus, to restore the 2n chromasome

2) spermatozoa fuse with the membrane of ovum: nucleus enter cytoplasm of ovum 3) monospermy: cortical reaction: cortical granules(located in cytoplasm of ovum) are released into perivitelline space, and cause zona reaction: change of ZP3 molecules in zona pellucide 4) formation of zygote(fertilized ovum) secondary meiosis complete: form second polar body male pronucleus fuse with female pronucleus, to restore the 2n chromasome

significance of fertilization 1)a new life begin (initiation of cleavage) 2)restoration of the diploid number of chromosomes: cross-over 3)determination of the sex of the new individual e ova (22+X)+ X-bearing spermatozoon girl e ova (22+X)+ Y-bearing spermatozoon boy *klinefelter's syndrome: 47XXY, 48XXXY

---significance of fertilization: 1) a new life begin(initiation of cleavage) 2)restoration of the diploid number of chromosomes: cross-over 3) determination of the sex of the new individual: ova(22+X) + X-bearing spermatozoon = girl ova(22+X) + Y-bearing spermatozoon = boy *klinefelter’s syndrome: 47XXY, 48XXXY