PSY 336 Lecture 6: Prenatal Development
Document Summary
Embryonic stage (3rd to 8th week: with implantation the zygote is now an embryo. Second is the chorion, which surrounds the embryo after 1 months. 5 to 10 milliliters after 8 weeks & to 1,000- 1,2000 milliliters. All vital organs and major body structures are formed. 1st is the amnion: grows over the embryo and is filled with amniotic fluid of tissue through which nutrients and waste pass between mother and embryo). 3 layers or cells start forming in 3rd week. After 21 days the ectoderm begins to form a groove that becomes a neural tube becomes the cns. Umbilical cord (2 arteries &1 vein) to supply blood to the embryo. Front portion of the tube becomes the brain & back becomes spinal cord. Fetus is growing (around 16 week the mother appears . Rapid growth especially during 3rd and 4th months other brain cells. 60 hours after conception: 4 cells are produced.
