ch. 4 Flashcards
(32 cards)
before birth, conception till birth
prenatal period
germinal, embryonic and fetal
prenatal periods
2 weeks, zygote, germ of cells, shortest period
germinal period
3 weeks - 8 weeks, embryo, the beginnings, rapid prenatal development
embryonic period
when do the layers of differentiated cells form
third week - embryonic period
digestive system, liver, panacreas, lungs
endoderm
circulatory system
mesoderm
hair, nails, skin, nervous system
ectoderm
9 weeks till birth, maturation, longest period
fetal period
day 6 of germinal period when it reaches 70 - 100 cells and enters the uterus
blastocyst
outer layer, placenta
trophoblast
emerges day 7 - 9 in germinal period gives the fetus nutrients, disappears in the eighth week of the embryonic period
yolk sac
when can you tell the sex of the baby
13 - 16th week
when do the lungs begin to practice expansion and contraction
13 - 16 week
begins in the spinal cord, during the 21 - 30 week in the fetal period
myelination
when are the lungs done developing
21 - 30 week of fetal period
3 layers of skin
endoderm, mesoderm, ectoderm
develops during 4th week, turns into CNS
neural tube
when does the heart begin to beat
fourth week - embryonic period
when does the neural tube begin to form the brain
fourth to fifth week - embryonic period
when does the heart form separate chambers
seventh week - embryonic period
when do the liver and spleen form
eighth week - embryonic period
when does biological sex begin to form
eighth week
dilation and effacement of cervix, birth and delivery of placenta
stages of childbirth
