普通胚胎学（PPT讲稿）General Embryology

GENERAL EMBRYOLOGY 1. Development of embryology 2. Germ cell and fertilization 3. Blastocyst and implantation 4. Formation of the germ layer 5. Differentiation of trilaminar germ and formation of embryo 6. Fetal membrane and placenta 7. Twins and multiple birth

GENERAL EMBRYOLOGY 1. Development of embryology 2. Germ cell and fertilization 3. Blastocyst and implantation 4. Formation of the germ layer 5. Differentiation of trilaminar germ and formation of embryo 6. Fetal membrane and placenta 7. Twins and multiple birth

Preembryonic period: 1st week to end of 2nd week fertilization to formation of bilaminar germ disc Embryonic period: 3rd week to end of 8th week formation of embryo Fetal period: 9th week to birth growth Perinatal stage: 26th week to 4 week after birth

Preembryonic period: 1st week to end of 2nd week fertilization to formation of bilaminar germ disc Embryonic period: 3rd week to end of 8th week formation of embryo Fetal period: 9th week to birth growth Perinatal stage: 26th week to 4 week after birth

ANimal c Plant Human

Human ？ Plant Animal

Development of embryology g Aristotle. B c 384-322 Semen+menstration g Harvey, 1651 All life from oocyte e Malpighi. 1675: A micro-chicken in an egg Leewenhoek, 1677: A micro-human in a sperm

Development of embryology Semen+menstration Harvey, 1651: All life from oocyte Malpighi, 1675: A micro-chicken in an egg Leewenhoek, 1677 : A micro-human in a sperm Aristotle, B.C 384-322

HAeckel. 1868 Biogenetic law sPemann, 1869-1941 Experimental embryology swIlmut. 1997 Dolly

Haeckel, 1868 Biogenetic law Spemann, 1869-1941 Experimental embryology Wilmut,1997 Dolly

Germ cell and fertilization Germ cell spermatozoon and ovum 1. spermatozoon Capacitation: In female reproductive tract, the sperms were enabled to bind to the zona pellucida receptors removal of glycoproteins(decapacitation factor which cover the sperms 2. Ovum secondary oocyte arrested at metaphase in the second meiotic division

Germ cell and fertilization Germ cell spermatozoon and ovum 1. Spermatozoon Capacitation：In female reproductive tract, the sperms were enabled to bind to the zona pellucida receptors. removal of glycoproteins (decapacitation factor) which cover the sperms 2. Ovum secondary oocyte arrested at metaphase in the second meiotic division

Fertilization: The process in which the spermatozoon penetrates into the ovum to form fertilized ovum In the ampulla of oviduct Ampulla site of fertilization (sperm cell penetrates oocyte) Uterine tube ocote rary Sperm cells deposited in vagina

Fertilization: The process in which the spermatozoon penetrates into the ovum to form fertilized ovum. In the ampulla of oviduct

Process of fertilization Sperm bind to sperm receptor ZP-3 induce Acrosome reaction: release of acrosomal enzyme Penetration and Cell release of acrosomal membrane nucleus acrosome enzyme of ovum sw

nucleus acrosome Penetration and release of acrosomal enzyme Cell membrane of ovum Process of fertilization Sperm bind to sperm receptor ZP-3 induce Acrosome reaction：release of acrosomal enzyme

ovum fertilized ovum sperm

ovum fertilized ovum sperm

c Zona reaction: Cortical granules-perivitelline space degrade zp-3, alteration of zona pellucida ->barrier for sperm penetration The second meiotic division of the secondary oocyte is rapidly lifted and the second ○ polar body is released leaving a haploid female nucleus

▪ The second meiotic division of the secondary oocyte is rapidly lifted and the second polar body is released, leaving a haploid female nucleus. Zona reaction: Cortical granules→perivitelline space →degrade ZP-3, alteration of zona pellucida →barrier for sperm penetration