Search results
Results from the WOW.Com Content Network
The part of the chorion that is in contact with the decidua capsularis undergoes atrophy, so that by the fourth month scarcely a trace of the villi is left. This part of the chorion becomes smooth, [2] and is named the chorion laeve (from the Latin word levis, meaning smooth). As it takes no share in the formation of the placenta, this is also ...
The trophoblast layer differentiates into amnion and the chorion, which then comprise the fetal membranes. [4] The amnion is the innermost layer and, therefore, contacts the amniotic fluid, the fetus and the umbilical cord. [5] The internal pressure of the amniotic fluid causes the amnion to be passively attached to the chorion. [4]
The yolk sac, amnion, chorion, and allantois are the four extraembryonic membranes that lie outside of the embryo and are involved in providing nutrients and protection to the developing embryo. [5] They form from the inner cell mass; the first to form is the yolk sac followed by the amnion which grows over the developing embryo. The amnion ...
The allantois (/ ə ˈ l æ n t oʊ ɪ s / a-LAN-toe-iss; [1] pl.: allantoides or allantoises) is one the extraembryonic membranes arising from the yolk sac.It is a hollow sac-like structure filled with clear fluid that forms part of the developing conceptus in an amniote that helps the embryo exchange gases and handle liquid waste.
The chorion and amnion membranes are labelled in this depiction of a growing fetus in the uterus. The amniotic sac consists of two parts: The outer membrane is the chorion. It is closest to the mother and physically supports the much thinner amnion. The chorion is the last and outermost of the membranes that make up the amniotic sac. [13]
In developmental biology, choriogenesis is the formation of the chorion, an outer membrane of the placenta that eventually forms chorionic villi that allow the transfer of blood and nutrients from mother to fetus. [1]
Chorionic villi are villi that sprout from the chorion to provide maximal contact area with maternal blood. They are an essential element in pregnancy from a histomorphologic perspective, and are, by definition, a product of conception. Branches of the umbilical arteries carry embryonic blood to the villi.
Membranes: allantois, chorion, amnion, and vitellus/yolk. Six commercial chicken eggs — view from the top against a white background An egg is an organic vessel grown by an animal to carry a possibly fertilized egg cell (a zygote ) and to incubate from it an embryo within the egg until the embryo has become an animal fetus that can survive on ...