Lecture 2: Prenatal Development Flashcards
What is the normal length of pregnancy?
around 40 weeks plus or minus 2 weeks
less than 37 weeks is preterm
more than 42 is post term (most are not allowed to go past that)
What is the division of prenatal life?
conception- 8 weeks
8-40 weeks- rest
What is time sequence of fetal development?
pre embryonic- 0-2 weeks
embryonic- 2-8 weeks
fetal period- 9-40 weeks
What are the three trimester?
1-13, 14-26, 27-39ish
By end of embryonic period what has happened?
- implantation complete
- early prenatal circulation
- formation of amniotic sac
What happens in embryonic period?
rapid cell division and early differentiation
beginning of heart, CNS, MS system
What are ectoderm cells?
NS, skin
What are mesoderm cells?
MS system, heart and cardio system, connective tissue
What are endoderm cells?
GI, respiratory structures
What is first system in fetus to reach full function?
Cardiovascular, heart contracts after 22 days
What is normal fetal circulation?
- ductus spinosus
- liver
- R- L side of heart though foramen ovale
- through ductus arteriousus over to lungs
What week is neural tube formed?
week 4
When can you tell if girl or boy?
Week 7
When does it look like human?
week 8
When do teratagens have biggest effect?
weeks 0-8
