Placenta Flashcards
What does the embryo form soon after implantation?
It forms an outer membrane called the chorion
What is the chorion?
2
The outer membrane of the embryo formed after implantation
It completely surrounds the amnion and the embryo
What is the function of the chorion?
It develops large chorionic projections called villi, which together with the blood vessels of the mother in the endometrium, form the placenta
What does the chorion surround?
The amnion and the embryo
What does the chorion produce?
Large chorionic projections called villi
What do the villi combine with to form the placenta?
The blood vessels of the mother in the endometrium
What makes up the placenta?
Villi from the chorion and blood vessels from the mother’s endometrium
When does the amnion form?
At implantation
When does the placenta start to function?
After four weeks
When does the placenta become fully functional?
Month 3
What makes the placenta differ from other animal organs?
It is the only organ that is formed from the tissues of two different individuals (embryo and mother)
What connects the embryo with the placenta?
The umbilical cord
Where does the the umbilical cord connect to the embryo?
At the navel
What is the function of the umbilical cord?
It connects the embryo to the placenta
How does the umbilical cord work?
It contains blood vessels that take blood from the embryo out to the placenta and back to the embryo again
What is the exchange function of the placenta?
It allows gases, nutrients, waste, antibodies, drugs and some hormones and micro-organisms to be exchanged (mainly by diffusion) between the blood of the mother and of the embryo
What are the three main functions of the placenta?
Exchange
Prevents mixing of blood
Produces hormones
What is exchanged between the blood of the mother and of the embryo through the placenta?
(7)
Gases
Nutrients
Waste
Antibodies
Drugs
Some hormones
Some micro-organisms
What is the main process involved in the exchange of materials in the placenta?
Diffusion
What is the prevention of blood mixing function of the placenta
(4)
The blood supplies of the mother and baby do not mix
Separation of the two blood supplies is essential because:
The blood groups might not be compatible, which would lead to damage to red blood cells
The blood pressure of the mother’s system would cause damage to the embryo
Does the mother and baby’s blood mix?
NO
Why is the Separation of the two blood supplies essential?
2
The blood groups might not be compatible, which would lead to damage to red blood cells
The blood pressure of the mother’s system would cause damage to the embryo
What is the hormone production function of the placenta?
It produces the hormone progesterone
Why is the placenta considered an endocrine gland?
Because it produces the hormone progesterone
