-
Preimplantation Period
Fertilization and implantation occur -
Period: to
Allison Craft- Prenatal Development
-
Week 2
- The egg has grown to over 3 times its original size
- development of the amniotic cavity and the chronic cavity
- bilaminar germ disc
-
Week 3
- The embryo is about the size of the head of a pin
- Ectoderm form neural plate
- Notochord formation
- Development of the primordial cardiovascular system
-
Week 4
- About the size of a poppy seed
- digestive tract splits into 3 sections
- frontonasal process
- brain development
- face and neck formation
-
Week 5
- About the size of a sesame seed
- Heart is starting to divide into chambers
- Primary palate is forming
-
Week 6
- Upper lip is formed
- Secondary palate is formed
- Nasal cavity
- arms and legs are budding
- Heart is beating twice as fast as ours
-
Week 7
- Tooth development begins
- Liver and appendix
-
Week 8
- baby is about the size of a raspberry
- breathing tubes stretch from the throat to the developing lungs
- dental lamina begins the stage of tooth development
