Fertilization, implantation, development of placenta and its function, amniotic fluid and abnormalities of placenta and cord

Fertilization, implantation, development of placenta and its function, amniotic fluid and abnormalities of placenta and cord

1. Acrosomal Reaction The acrosomal layer of the sperm become reactive and release the enzyme hyaluronidase known as the acrosome reaction. It disperses the corona radiate (outer layer of ovum) allowing access to the zona pellucida

2. The plasma membrane of the sperm and oocyte fuse. The oocyte at this stage complete and second meiotic division and becomes mature, the pronuclei has 23 haploid chromosomes. Male and female pronuclei fuses to form a new nucleus that is a combination of the genetic material from both the sperm and the oocyte diploid cell

3. Development of Zygote The male and female gametes each contribute half the complement of the chromosomes to make a total of 46. the new cell is called zygote. The zygote, thus formed, contain both the paternal and maternal genetic materials. Sex of the child is determined by the pattern of the sex chromosome supplied by the spermatozoon If the spermatozoon contain X chromosome, a female embryo (46,XX) is formed, if it contain a Y chromosome , a male embryo (46, XY) is formed.