2. Condition of fertilization ① Normal ovum ② Normal sperm sufficient numbers ③ Certain time 12-24h 4 Free reproductive tract
2.Condition of fertilization ① Normal ovum ② Normal sperm sufficient numbers ③ Certain time 12-24h ④ Free reproductive tract
3. Significance of fertilization ① A new life ② Diploid inheritance and aberrance 8 Sex determination
3.Significance of fertilization ① A new life ② Diploid inheritance and aberrance ③ Sex determination
Formation of blastocyst and implantation Cleavage and formation of blastocyst 1. Cleavage: early division of fertilized egg 2. Blastomere: daughter cells from cleavage 3. Morula: 12 to 16-cell stage, enclosed in the zona pellucida like morus 4 Blastocyst: about 100 blastomeres blastocoele, inner cell mass and trophoblast polar trophoblast
Formation of blastocyst and implantation Cleavage and formation of blastocyst 1. Cleavage： early division of fertilized egg 2. Blastomere：daughter cells from cleavage 3. Morula：12 to 16- cell stage, enclosed in the zona pellucida, like morus 4. Blastocyst：about 100 blastmeres blastocoele、inner cell mass and trophoblast polar trophoblast
Phase of cleavage ,量 Fertilized 2-cell stage egg 18~36h 4-cell 8-cell stage stage 36~48h 48~60h
Phase of cleavage Fertilized egg 2-cell stage 18~36h 4-cell stage 36~48h 8-cell stage 48~60h
Morula D 12 to 16-cell stage The third day
Morula 12 to 16-cell stage The third day