What does chorion mean in biology?
chorion, also called Serosa, in reptiles, birds, and mammals, the outermost membrane around the embryo. It develops from an outer fold on the surface of the yolk sac.
What is the origin of chorion?
The chorion is derived from trophoblastic ectoderm and extraembryonic mesoderm (somatopleure). There is an intimate association between the forming chorion and amnion. These form by folding in domestic animals and by so-called cavitation in humans, mice, and rats.
What is the chorion 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 the placenta?
The fetal part of the placenta is known as the chorion. The maternal component of the placenta is known as the decidua basalis.
What is chorion and chorionic villi?
The chorion undergoes rapid proliferation and forms numerous processes, the chorionic villi, which invade and destroy the uterine decidua and at the same time absorb from it nutritive materials for the growth of the embryo. They undergo several stages, depending on their composition. Stage.
What does chorion anterior mean?
The placenta attaches to the wall of your uterus, and its position can be anywhere — front, back, right, or left. If the placenta attaches to the back of the uterus, it’s known as a posterior placenta. If it attaches to the front of the uterus, it’s called an anterior placenta.
What is fetal chorion?
The chorion is the outermost fetal membrane around the embryo in mammals, birds and reptiles (amniotes). It develops from an outer fold on the surface of the yolk sac, which lies outside the zona pellucida (in mammals), known as the vitelline membrane in other animals.
What is the difference between posterior and anterior placenta?
The placenta attaches to the wall of your uterus, and its position can be anywhere — front, back, right, or left. If the placenta attaches to the back of the uterus, it’s known as a posterior placenta. If it attaches to the front of the uterus, it’s called an anterior placenta. Both types are common.
What baby if placenta is posterior?
A posterior placenta means that your placenta has implanted onto the back of your uterus. This means that you have the advantage of feeling your baby’s movements earlier and stronger as well as allowing the baby to get into the most optimum position for birth (spine at the top of your belly – anterior).
What is a chorion?
The whole being surrounded by two membranous coverings, the outer one called the chorion, and the inner one the amnion. Twins coming from one egg have the same chorion and can thereby be diagnosed as such. It also sometimes brings away part of the amnios, and even the chorion, upon its head like a cap.
What are the two layers of the chorion?
The chorion in turn comprises two layers: a double layer of trophoblasts on the outer side and the mesoderm on the inner side, in contact with the amnion. The outer layer of the chorion is made of trophoblasts (also known as the trophoblast ), which are the first cells to differentiate once the mammalian egg has been fertilized.
What is the function of the chorion in the uterus?
The chorion has two main functions: protect the embryo and nurture the embryo. To protect the embryo, the chorion produces a fluid known as chorionic fluid. The chorionic fluid lies in the chorionic cavity, which is the space between the chorion and the amnion.
What is the difference between amniote and chorion?
chorion – the outermost membranous sac enclosing the embryo in higher vertebrates (reptiles, birds and mammals) amniote – any member of the Amniota.