KINESIOL 2Y03 Lecture Notes - Lecture 3: Zona Pellucida, Pronucleus, Zp3
Document Summary
Fertilization begins when a sperm penetrates an oocyte and then it ends in the creation of a zygote. Sperm have up to 48 hours of energy stored to stay alive and viable. There is a 3 day window to become pregnant [2 days prior and. 1% of sperm make it into the cervix, in the uterine cavity which is the site of fertilization. Fertilization: to fertilize an egg, sperm must penetrate the corona radiata and the zona pellucida, which is outside of the oocytes plasma membrane. The longest process is the first division and it takes 6 hrs. Haploid nucleus in the head of the sperm becomes the male pronucleus and the haploid nucleus of the fertilized ovum becomes the female pronucleus. Merging of the two is called syngamy, diploid zygote is formed. Capacitation: the enzymes of the sperms acrosome along with tail movement allow the sperm to penetrate the corona radiata.
