Friday, September 26, 2008
Speaking of calendars, here is a fantastic library of Pregnancy Ultrasound Photos Week by Week for Fetal Development.
This past week I learned about how gametes (sex cells- ovum and sperm) are formed in meiosis and in particular a process called Gametogenesis. I know, pretty basic biology but I was so interested to learn that the one egg cell takes all of the cytoplasm from the cell divisions- creating one big fat egg that will then be able to begin to divide into a multi-cellular organism (eventually an embryo) once fertilized- and thee polar bodies that are nothing but pure genetic material (and eventually dissolve). Sperms too are almost pure genetic material with swimming tails.
Also fascinating, Oogenesis, is started in weeks 4-8 in embryonic development. A baby girl will be born with all of her lifetime eggs. Where as an adult male can produce over 100million sperm per day.
Here is a medical animation of an egg fertilization.
Posted by Kate Zondervan at 9:08 AM