Reproduction Lab

There are many stages to the fetal development. Some are minute and some are monumental, depending on how one sees things. Even so, it is an ongoing process and changes are not sudden. There are landmarks that can tell you what and when certain developments happen. Here are some that I find very interesting.

1. At 4 weeks the embryo is just two layers of cells, the epiblast and the hypoblast.
2. A lot happens in just the "first month" (beginning at about 4 weeks after conception) by week six, just two weeks after the embryo was but two layers of cells, the embryo is forming vocal chords and a tongue. It already has fingers and will begin to move its arms and legs in this week. The heart is apparent by this time, too.
3. At 8 weeks the brain has begun to connect nerve paths to other parts of the body. The baby has knee joints and definitive, flexed wrists. The baby also has formed eyelids that virtually cover the eyes.
4. By 11 weeks the baby has developed bones. This week the bones will have begun to harden. Teeth buds will also have formed beneath the gums.
5. By 13 weeks the baby will have a unique set of fingerprints. It will also have the abilityto urinate, as it begins to expel amniotic fluid it has swallowed.
6. By 16 weeks the circulatory system is developed and the baby's heart is busy pumping.
7. By 18 weeks the baby has begun to move about regularly.
8. At 24 weeks the baby started to develop taste buds and what would life be like without those? Also thelungs have developed more and the bronchial tree is noticeable.
9. Because a baby's lungs are fully developed at this point, baby's born at 34 weeks have a 99% survival rate!10. In the 40th and 41st weeks the baby is as developed as it will be before birth. It is ready to make the trip into the outside world. Its skull plates have separated to make it easier for the head to go through the birth canal.