Ebryology 1 Flashcards
during what weeks does the pre embryonic phase take place
0-3 weeks
during what weeks does the embryonic phase take place
4-8 weeks
each sperm and ovum is genetically unique true or false
true
is a zygote a diploid or haploid cell
diploid
what is formed between the stages of a zygote and a blastocyte
morula
After the morula what is formed
blastocyte
what is the morula
a solid mass of cells
why does a blastocytic cavity form in the morula
as the number and size of cells increase, getting nutrition to the central core of the cells becomes difficult therefore the cavity forms to aid the process
what is the outer lining of cells of the morula called
trophoblast
what is an ectopic pregnancy
a pregnancy in which the fetus develops outside the womb, typically in a fallopian tube.
at what week does the placenta begin to develop
week 2 of pre embryonic phase
when does implantation occur (when the blastocyte begins to burrow into the uterine wall)l
at 7 days
what are the cells that form the outer cell mass referred to as
trophoblast
how many layers does the trophoblast divide to form
2
what does the trophoblast ultimately form
the chorion
what is the chorion and what is its function
it is a membrane that develops at the beginning of pregnancy between the fetus and the mother.
it is involved in the implantation process and forms part of the placenta.
what does the chorion secrete that can be used to detect pregnancy
human chorionic gonadotrophin
what is the decidua basalis
part of the endometrium deep to the implanted conceptus
human chorionic gondaptropin helps to maintain what
the endometrium
what happens to the inner cell mass of the blastocyte
form a 2 layered flat disc called the bilaminar disc
the bilminar disc separates 2 cavities, what are these cavities
amniotic cavity
yolk sac
around what week does the bilaminar disk form
second week
by what week is the placenta mature
by 18-20 weeks
