Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
23 Cards in this Set
- Front
- Back
|
The Fetal Period
|
weeks 9 thru 38. Growth is the main feature of this 30 week period of time. The Fetal period ends at birth.
|
|
|
embryonic period
|
first 8 weeks.. during this period all the organs are in place and the embryo starts looking like a human.
|
|
|
conception
|
happens in the falopian tube.
|
|
|
zygote
|
fertilized oocyte - moves towrds the uterus.
|
|
|
blastomeres
|
daughter cells formed from zygote.
|
|
|
morula
|
cluster of 16 cells
|
|
|
blastocyst
|
fluidfilled structure - start dividing cells up (about 60 cells)
|
|
|
implatation process
|
takes about a week. the trophoblast erodes the wall of the uterus till its embedded firmly.
|
|
|
inner cell mass
|
a cluster of cells on one side of the blastocyst cavity. it will form the embryo.
|
|
|
trophoblast
|
will form the placenta, the structure that transfers nutrients from mother to fetus.
|
|
|
bilaminar embryonic disc--
|
inner cell mass divides into two sheets; epiblast & hypoblast
|
|
|
amniontic sac
|
formed by an extension of epiblast
|
|
|
amnion
|
outer membrane of the amniontic sac
|
|
|
amniotic sac cavity
|
inner membrane forms; filled with amniotic fluid. contains info for checkin for birth deffects and diseases before birth
|
|
|
yolk sac
|
formed from an extension of hypoblast -- digestive tube forms from yolk sac --- some tissues give rise to earliest blood cells & blood vessels
|
|
|
primitive streak
|
raised groove on the dorsal surface of the epiblast
|
|
|
gastrulation
|
a process of invagination of epiblasts -- forms the 3 primary germ layers
|
|
|
endoderm
|
formed from migrating cells that replace hypoblast
|
|
|
mesoderm
|
formed between epiblast & endoderm
|
|
|
ectoderm
|
stays on the dorsal surface
|
|
|
primitive streak
|
germ layer formation -- epiblast cells migrate inward at the streak, displace the hypoblast and become the endoderm
|
|
|
notochord
|
defines the body axis (the midline) -- is the site of the future vertebral column
|
|
|
primitive NODE
|
swellin at the end of the primitive streak
|
