Lecture 8- Embryology Flashcards
What are the from fertilisation to birth stages?
Pre-embryonic (0-2 weeks) cells to alllow embryonic development
Embryonic (3-8) develop structures
Fetal (9-38) grow structures
How long is pregnancy?
Generally calculated from last period so 38 weeks plus the two extra.
40 plus or minus two is considered normal
Where is the egg fertilised?
Ampulla- part of Fallopian tube
What is the fertilllised oocyte called?
Zygote
Where is the bet implantation site?
Posterior uterine wall
How long are the oocyte and sperm viable for
1 day and 3 days
What is the function of the zone pullicida?
Prevents more sperm from getting in..
What is pre implantation genetic diagnosis?
For in vitro morulas can take a cell and test for serious genetic diseases. Cells of morula are totipotent and identical so no problem removing one
After compaction what do cells become?
Pluripotent
What happens in week one?
See lecture
What does the bilaminar disk consist of?
Hypoblast and epiblast
What has happened at the end of two weeks?
You have a blastocyst with an amniotic sac, a yolk sac and a bilaminar disk consisting of an ambryoblast and hypoblast. This is surrounded by a chorionic cavity and connected via a connecting stalk to a cytotrophobllast and synciotrophoblast. It has been inserted into the endometrium and a fibrin plug has filled the gap where it entered.
Name two conditions linked to implantation defects?
Ectopic pregnancy and placenta praevia.
When does uteroplacental circulation begin?
Week 2 day 12
What are chorionic villi?
Projections from chorion that provide maximal contact area with maternal blood.
