45 workbook 2 Flashcards
cellular outermost extraembryonic membrane, composed of trophoblast lined with mesoderm
chorion
products of conception from fertilizatoin through implantation; the zygotic stage of pregnancy lasts for approxiamtely 12 days after conception
zygote
vascular structure withint he fetal liver that connects the umbilical vein to the inferior vena cava and allows the oxygenated blood to bypass the liver and return directly to the heart
ductus venosum
functional structure within the normal ovary that is formed from cells lining the graffian collicle after ovulatio; it produces extrogen and progesterone and may become enlarged and appear cystic during early pregnancy
corpus luteum
inferior segment of the uterus which normally is more than 3.5cm long during pregnancy and decreases in lenght during labor
cervix
connecting lifeline between the fetus and the placenta; it contains two umbilical arteries which carry deoxygenated fetal blood and one umbilical vein which carries oxygenated fetal blood encases in Wharton’s jelly
umbilical cord
developing individual from implanation to the end of the 9th week of gestation
embryo
smooth membrane enclosing the fetus and amniotic fluid; it is loosely fused with the outer chorionic membrane except at the placental insertion of the umbilical cord, where it is contiguous with the membranes surrounding the umbilical cord
amnion
thin expanded lower portion of the uterus that forms in the last trimester of pregnancy
lower uterine segment
circular structure within the gestational sac seen sonographically between 4 and 10 weeks gestational age; supplies nutrition, facilitates waste removal and is the site of the early hematopoietic stem cells in the embryo
yolk sac
a 40-week pregnancy is divided into three 13 week periods from the first day of the last normal period
trimester
structure lined by the chorion that normally implants within the uterine deciduas and contains the developing embryo
gestational sac
