conception and fetal developmental teratogen Flashcards
developing embryo becomes a hollow ball of cells and is called a
blastocyst
where in the fallopian tube is the egg fertilized
outer 1/3rd
how many days does it take for the zygote to make it through the fallopian tube
about 4 days
outer cell mass of a developing zygote that develops into the placenta, helps with implantation
trophoblast
inner cell mass of a developing zygote that develops into the fetus (also called embryonic stem cells)
embryoblast
what day after fertilization does the zygote implant in the uterus (when its implanted its called an embryo)
days 7-10
what are 3 germ cells
ectoderm
mesoderm
endoderm
process where zygote develops germ cells
gastrulation
germ layer that develops outermost layer: skin, nervous system, spinal cord, brain, hair, eye lens
ectoderm
germ layer that develops middle layer: skeleton, muscle, connective tissue, blood vessels, kidney
mesoderm
germ layer that develops innermost layer: lining of GI tract, lungs, bladder, pancreas, thymus, liver
endoderm
when is baby referred to as zygote
immediately after fertilization until implantation
when is baby referred to as embryo
implantation (around day 10) to 8 weeks
when is baby referred to as fetus
8 weeks (post conception) to birth
when is baby most vulnerable to malformation and teratogens
when it is an embryo (10 days - 8 weeks)
first organ of embryo to start functioning (3-4 weeks after conception)
heart
nutrient important for spinal cord development of embryo
folic acid (all sexually active women of childbearing age should take folic acid supplements)
time since first day of last normal menstrual period
gestational age
time since conception (time since first day of last normal menstrual period minus 2 weeks)
conceptual age
2 structures included in fetal membranes
chorion
amnion (closest to baby)
sources of amniotic fluid (3)
maternal blood
resp and GI secretions from fetus
fetal urine
functions of amniotic fluid (6)
- thermal regulation
- cushion
- facilitations symmetrical growth and development
- allows fetal lung development (breathes in and swallows the fluid)
- source of oral fluid
- waste repository
what degrees C and F are considered fever
- 4 F
38. 0 C
volume of amniotic fluid at term
700-1000 mL
critical piece of fetal assessment
volume of amniotic fluid
how many mL is oligohydramnios of amniotic fluid (worried about perfusion, renal anomaly, leak in membranes)
<300 mL
how many mL is polyhydramnios of amniotic fluid (sometimes associated with GI anomaly)
> 2 L
what is LS ratio (tested by amniocentesis)
ratio of lecithin and sphingomyelin in amniotic fluid
ratio of 2:1 indicates mature fetal lungs
how many vessels in umbilical cord
2 arteries
1 vein