Embryology 1 (Early Stages) Flashcards
What do fimbria do?
During ovulation, they sweet the oocyte into the ampulla where it may be fertilized.
Where does a developing embryo typically implant?
The posterior wall of the uterus
Where does fertilization typically take place?
Ampulla
What is the Zona Pellucida?
Sphere of maternal tissue that surrounds the very early developing embryo (Morula). Made of glycoproteins.
Who is a really awesome guy in our class?
Kyle
The morula includes two primary parts. What are their names?
The Trophoblast and the Inner Cell Mass
What is Early pregnancy factor?
An Immunosuppressant secreted by trophoblast cells that turns pregnancy tests positive.
How does the early embryo derive nourishment?
Absorption of secretions from uterine glands
What are of the embryo typically first attaches to the uterus?
The embryonic pole
When becoming a blastocyst, the trophoblast forms two distinct layers. What are they?
The cytotrophoblast (inner layer) and syncytiotrophoblast (outer layer)
Label
What level of the embryo invades the uterus?
Syncytiotrophoblast
What is thought to activate the clavage stage in the blastomere?
Early Pregnancy Facter (EPF)
What is the name of the fluid filled space on the inside of a blastomere?
Blastocoele
Following implantation, the row of cells facing the blastocoele become this layer
Embryonic endoderm
What cell layer comprises the primitive endoderm?
The Hypoblast
The invasion of the syncytiotrophoblast allows what to begin to occur?
Nourishment from maternal tissues
By the end of the 2nd week, the synytiotrophoblast begins to produce what hormone?
Human chorionic gonadotropin
What is the amniotic cavity?
A cavity at the embryonic pole between the ICM and the cytotrophoblast
What cells line the amniotic cavity? What layer do they differentiate from?
The Amnion. The Cytotrophoblast.
The ICM forms a flattened disc with what two layers?
Epiblast (amniotic side) and Hypoblast (in blastocyst cavity)
During week two of development, what cells line the bastocoele?
Cells from the hypoblast, which form Heuser’s membrane
What layer develops into the extraembryonic mesoderm? Where is this membrane located?
Cytotrophoblast. Aroudn the outside and btw the amnion and yolk sac.
Cavities in the extraembryonic mesoderm. These coalesce to to form what structure?
Extraembryonic coelom.
