| Question |
Answer |
| the trophoblast above the epiblast produces what new layer? why? |
syncytiotrophoblast, produces progesterone |
| all cells not becoming a part of the syncytiotrophoblast become what? |
cytotrophoblast |
| how do syncytiotrophoblast nuclei proliferate if they are amitotic? |
as the cytotrophoblast cells divide, they fuse with the syncytiotrophoblast to donate nuclei |
| the embryoblast laminates into what 3 cell layers? which two are the bilaminar layer? |
the amnion, epiblast, and hypoblast; bilaminary layer is the hypoblast and epiblast |
| what is the amnion? |
the thin membrane that forms along the interior of the cytotrophoblast |
| what cells comprise the epiblast? why is this important? |
high columnar cells; this is the entire fetus with the exception of the primordial germ cells |
| the hypoblast produces what structure? what cells is it comprised of? |
the yolk sac; it is comprised of small cuboidal cells |
| after the blastocyst embeds, what cells close the hole on the endometrial surface? |
fibrin coagulum |
| the hypoblast spreads along the inner surface of the endometrium to form what? |
extraembryonic endoderm |
| where is the primary yolk sac? |
bound by the extraembryonic endoderm and the hypoblast |
| spaces formed in the syncytiotrophoblast are called what? what is this period called? |
trophoblastic lacunae; lacunar stage |
| what is the new layer that forms between the cytotrophoblast and the extraembryonic endoderm? |
extraembryonic mesoderm |
| extraembryonic lacunae expand to form what? |
chorionic cavity |
| the extraembryonic mesoderm layer lining the yolk sac is what? |
splanchnic extraembryonic mesoderm |
| the extraembryonic mesoderm layer lining the cytotrophoblast is what? |
somatic extraembryonic mesoderm |
| what are the 3 layers of the chorion? |
somatic mesoderm, cytotrophoblast, and syncytiotrophoblast |
| what primordial structure becomes the umbilical cord? |
the connecting stalk |
| placental circulation begins to develop where? |
at the embryonic pole |
| syncytiotrophoblast erodes the endometrium endothelial lining of the maternal capillaries to produce what? |
sinusoids |
| what process has glandular secretions causing endometrium surrounding the embryo to become edematous with glycogen and lipids? |
the decidua reaction |
| what does the decidua region of the endometrium develop into? |
maternal component of the placenta |
| what is the portion of the primary yolk sac that is pinched off from the embryo? |
the exocoelomic cyst |
| increased blood flow to the lacunar spaces can produce bleeding when? |
28th day of menstrual cycle |
| what term means to have multiple nuclei within an extended, continuous cytoplasm? |
synctytium |
| A fluid filled cavity develops between the amnion and epiblast known as what? |
amniotic cavity |
| during amniocentesis, what marker is being checked for? what might this indicate if found? |
alpha-fetoprotein; developmental defect |
| where do extraembryonic lacunae develop? |
extraembryonic mesoderm |
| after the primary yolk sac pinches off the exocoelomic cyst, what is it then called? |
secondary yolk sac |
Cardio Block2anatomy
