implantation of the blastocyst and gestation Flashcards
What is implantation?
The process where the blastocyst embeds itself into the endometrium.
How does the blastocyst implant into the uterus?
It secretes enzymes that soften the uterine wall, allowing it to sink in.
What two extra-embryonic membranes develop after implantation?
Amnion and Chorion.
What is the function of the chorionic villi?
They extend into the endometrium and form part of the placenta.
When is the embryo called a foetus?
After 12 weeks of development.
What is the role of amniotic fluid?
Protects against mechanical injury (shock-absorber)
Prevents dehydration
Maintains temperature
Allows free movement
What is the function of the umbilical cord?
It connects the foetus to the placenta and transports substances.
What does the umbilical vein carry?
Oxygenated blood, nutrients, and water from the mother to the foetus.
What do the umbilical arteries carry?
Deoxygenated blood and waste from the foetus to the placenta.
Why doesn’t maternal and foetal blood mix?
The placenta allows diffusion of substances without direct blood contact.
What are the main functions of the placenta?
Attachment of foetus to mother
Nutrient and gas exchange
Waste removal
Secretes progesterone after 12 weeks
