M1: Development of Placenta Flashcards
Is dependent on the placenta for pulmonary, hepatic and renal functions
Fetus
Early trophoblast formation
Implantation
Maternal blood spurts from ___________ into the placental __________ and bathes the outer _________.
Uteroplacental vessels. Intervillous space. Syncytiotrophoblasts.
Fetal and maternal blood are not mixed in this
Hemochorial placenta
There is a _______ system that links mother and fetus
Paracrine
Juxtaposition of the maternal decidua _______ and the extraembryonic chorion laeve.
Parietalis
Human placental formation begins with the
Trophoectoderm (morula)
Plays a critical part at the fetal maternal interface. Invasiveness promotes implantation. Nutritional role for the conceptus and maternal physiological adaptations, pregnancy maintenance.
Trophoblasts
Differentiation occurs ______ postfertilization.
8th day
Outer multinucleated
Syncytiotrophoblast
Inner, mononuclear. Germinal cells for syncytium. Well-demarcated cell border, single nucleus, undergoes DNA synthesis and mitosis.
Cytotrophoblast
Villous trophoblast: transports O2, nutrients
Chorionic villi
Migrates into decidua, myometrium. Penetrates maternal vasculature.
Extravillous trophoblasts
Extravillous trophoblasts: interstitial bed giant cells
Interstitial trophoblast
Extravillous trophoblasts: spiral artery lumen
Endovascular trophoblast
Low resistance blood flow
Spiral arteries
Invade, transforms spiral arteries.
Endovascular trophoblasts
Invade the decidua. Surrounds spiral arteries.
Interstitial trophoblasts
Day in which blastocyst is enclosed in EM
10th day
As the embryo enlarges, more maternal decidua basalis is invaded by _________.
Syncytiotrophoblasts