The Placenta Flashcards
What are the fetal membranes
chorion, amnion, yolk sac and the allantois
functions of the placenta
protection, nutrition, respiration, excretion and hormone production
the __________are part of the fetal placenta unit
suprarenal gland
The fetal part of the placenta arises from
chorionic sac
the maternal part of the placenta arises from
endometrium
the maternal part of the placenta is called
decidua
What is the decidua reaction ?
with increasing levels of progesterone, the connective tissue cells of the decidua become enlarged and pale staining and help protect the uterus against complete invasion of the synctiotrophoblast
decuda basalis
deep to the fetus (base of implantation site)
decidua capsularis
overlying the fetus (covers the implantation site)
decidua parietalis
everything else (part of the decidua not implantation site or covering of it
what does the trophoblast give rise too ?
cytotrophoblast and syncytiotrophoboblast
what forms the layers of the chorion ?
somatic layer of extraembryonic mesoderm and layers of trophoblasts
chorionic villi will attacht to the _____ via the ____________ and serves to anchor the chorionic sac
decidua basalis, cytotrophoblast
what four things does the chorionic membrane consist of
syncytiotrophoblast, cytotrophoblast, embryoonic ct, and endothelium of fetal vessels
what does the fetal part of the placenta do ?
seperates the fetus from the endometrium of the uterus
what do the fetal membranes include
chorion, amnion, yolk sac, and the allantois
what fills the primary villi to form the secondary villi
somatic mesoderm
the presence of blood vessels designates what ?
tertiary villi
the fetal placenta is the
villous chorion
maternal placenta is
decidua basalis
where is the intervillous space derived from ?
lacunar network that formed in the syncytiotrophoblasts in the second week
the intervilous space is drained by what veins
endometrial veins
amniochorionic membrane
fusion of amniotic and chorionic sac (ruptures during labor) and membrane fuses with decidua capsularis and then adheres to decidua parietalis obliterating the uterine lumen
what does the placenta membrane consist of
syncytiotrophoblast, cytotrophoblast, embryonic connective tissue, and endothelium of the fetal vessels
beneficial things that cross the placenta
metabolic gases, oxygen, carbon dioxide, water, glucose, amino acis, free fatty acids, vtamins, urea, uric acid, bilirubin, electrolytes, rBCs, serum proteins, alphafetoprotein, steroid hormones, immunogloulin A and G
things that cross the placental membrane that hare harmful
CO viruses many drugs anti-RH antibodies toxoplasma gondii, and treponema palladium
the umbillical cord has
two arteries and one vein
placenta accreta
placenta adheres to myometrium
placenta percreta
penetrates the full thickness of the myometrium and fails to seperate from the uterine wall
erythroblastosis fetalis
Rh incompatability between mother and fetus
mom has been exposed to fetal blood, makes antibodies IgG against fetal antigen and can cross the placenta, if there is a future pregnancy with Rh incompatability, antibodies can cross and attack fetal RBC’s causing anemia and edema
somatic layer of extraembryonic mesoderm and layers of the trophoblast form
chorion
