The Placenta Flashcards
What is the chorion?
The outer most membrane of the embryo
What is the corpus luteum?
A hormone secreting structure which develops in the ovary after the ovum has been discharged
Degenerates if a pregnant doesn’t occur
Where are the chorion and placenta derived from?
Trophoblast
Where does the embryo implant?
In the decidua of the endometrium
What is the name of the inner cellular layer of the trophoblast?
Cytotrophoblast
What is the role of the chorionic villi?
They project into the decidua basalis(layer of the endometrium)
- the ones with the best blood supply become anchorage for the placenta to hold it in place
- those that don’t break down and become the chorion (the outer amniotic membrane)
What does the placenta depend on?
Maternal blood for oxygen and nutrients and removal of waste products
What is the role of the placenta in excretion?
Removing waste products of metabolism, CO2 and heat cross from the fetus to the mother
What is the role of the placenta regarding nutrition?
- Control active transport of glucose, iron and vitamins
- Metabolizes proteins, fats, carbohydrates
- Stores glycogen which can be easily converted to glucose
Name the 3 stages of implantation
Apposition
Adhesion
Invasion
List the 5 functions of the placenta
- Respiration
- Nutrition
- Excretion
- Hormone production
- Protection
Define the corpus luteum
A glandular mass formed in the ovary at the site of a ruptured ovarian follicle immediately after ovulation.
Where does the placenta embed into?
The decidua
What do the chorionic villi do as they penetrate the decidua?
They erode the walls of the maternal blood vessels, this allows pools of blood known as sinuses to form
