Flashcards in 20 Development (Lecture) 8 Deck (23):
growth prior to birth 9 mo
3 mo x 3
Pre-Embryonic phase begins ? and ends?
Begins at fertilization and ends at implantation
occurs in ampulla of fallopian tube union of sperm and egg.
is a fertilized egg
First 30 hours after fertilization
cell divsion with out cell growth
solid ball of cells that enters the uterus
hollow sphere with a small mass of cells floats in uterus. this is what implants into wall of uterus.
Gestation / Pregnancy begins...
Amnion, Yolk, Chorion (external)
fluid filled sack that embryo developes in
structure that will produce embrionic blood
membrane across which mother and baby exchange material becomes placenta
genectic specialization of embrionic cells
This is the 4th extra embrionic membrane. this will serve as a temporary bladder for waste. later it becomes part of the cord.
4 weeks becomes arms and legs
Embryonic heart contractions
begins at week 8
*All organ systems present after
Ossification occurs week 8
cartilage becomes bone
Identical zygote splits