When can the term fetus be correctly used?
Birth is imminent and occurs around the 38th week after fertilization. The fetus is considered full-term between weeks 36 and 40, when it is sufficiently developed for life outside the uterus.
Which membrane plays the greatest role in nutrient and waste exchange *?
Chorion
Which extra embryonic tissue contributes to protection of the human fetus?
The amniotic cavity becomes filled with amniotic fluid. The amnion is an important extraembryonic membrane throughout development. The fluid in this sac supports and protects the fetus against mechanical shock and supplies water and other materials to the fetus.
What does Allantois become?
In placental mammals, the allantois is part of and forms an axis for the development of the umbilical cord. The embryonic allantois becomes the fetal urachus, which connects the fetal bladder (developed from cloaca) to the yolk sac. The urachus removes nitrogenous waste from the fetal bladder.
Is Allantois the yolk sac?
The allantois is an extension of the posterior wall of the yolk sac. Its exact role in development is unclear, though its blood vessels do become the umbilical blood vessels. It gives rise to a structure called the urachus which contributes to the superior wall of the urinary bladder.
What is the difference between placenta and Chorion?
The main difference between chorion and placenta is that chorion is the outermost fetal membrane, covering the embryo of mammals, reptiles, and birds whereas placenta is the temporary organ that connects the developing fetus to the uterine wall through umbilical cord in mammals.
What is the difference between amnion and Chorion?
The amnion is found on the innermost part of the placenta. It lines the amniotic cavity and holds the amniotic fluid and the developing embryo. The chorion, on the other hand, is the outer membrane that surrounds the amnion, the embryo, and other membranes and entities in the womb.
What role does Chorion tissue play in fetal development?
The chorion is one of the first membranes that forms during a pregnancy and is composed of two layers, the mesoderm and trophoblasts. The chorion is crucial to the fetus, since it provides life support by providing for a pathway for the exchange of gases, blood, and waste between the mother and the fetus.
What is the Chorion and what is its function?
The functions of the chorion are to protect and nurture the embryo. The chorionic fluid protects the embryo from shock, and the chorionic villi allow the exchange of nutrients, oxygen and waste products with the mother.
Is the Chorion part of the placenta?
Placental Membrane The fetal part of the placenta is known as the chorion. The maternal component of the placenta is known as the decidua basalis.
What fetal tissue contributes to the formation of the placenta?
The fetal component of the placenta, called the chorion frondosum, develops from the fetal blastocyst, while the maternal component, called the decidua basalis, develops from the maternal uterine tissue. Placental development is initiated after fertilization and implantation.
What fetal tissue contributes to the formation of the placenta quizlet?
The trophoblast becomes the placenta and chorion, while the embryoblast becomes the embryo, amnion and umbilical cord. What is the fetal contribution to the placenta? The extraembryonic mesoderm, which becomes the chorion.
Which cell is present in placenta?
Placenta villi are composed of three layers of components with different cell types in each: (1) syncytiotrophoblasts/cytotrophoblasts that cover the entire surface of the villous tree and bathe in maternal blood within the intervillous space; (2) mesenchymal cells, mesenchymal derived macrophages (Hofbauer cells), and …