Embryo Weeks 0-3

How long is early development

0-2 weeks

How long is embryonic period

3-8 weeks

How long is fetal period

9w-end

Spermatogenesis

spermatogonia, 1 spermatocyte, 2 spermatocyte, spermatid, spermatozoid

what does corpus leutum excrete

estrogen and progesterone

Oogenesis

oogonia, 1 oocyte, 2 oocyte, definitive ooctye

Trisomy 21

downs syndrome

klinefelter’s

xxy

trisomy 18

Edwards’s syndrome

turner’s syndrome

missing sex chromosome

Triple x

xxx

Angelman’s

microdeletion of maternal chromosome

Prader-willi

microdeletion of paternal chromosome

Trisomy 13

cleft lip

placenta previa

implantation site too close to cervix

placental abruption

placenta detaches

placenta accretas

too deep in uterine wall

placenta incredas

too deep in uterine muscle

placenta percreta

too deep into organ

what does extraembryonic mesoderm make

sematapluric layer and splanchnopleuric layer

somatapluric layer

against trophoblast

Splanchnoplueric layer

against yolk sac

what does syncytiotrophoblast do?

release hcg

what is chorion composed of

mesoderm, cytotropoblast, syncytiotropoblast

what does notocord do

direct cns development, forms vertebral column, defines midline, forms nucleolus pulposus