Embryology: Week 2 Flashcards
What is the bilaminar disc and what does it come from?
The bilaminar disc forms in week 2 and comes from the inner cell mass. During week 2, the inner cell mass will divide into the hypoblast and epiblast.
What is only formed in week 2 of the embryonic stage?
The extraembryonic endoderm which comes from the hypoblast.
What is formed from the extraembryonic endoderm?
The extraembryonic endoderm made from the hypoblast will form the prechordal plate (mouth and anal cavity), primary yolk sac, the secondary yolk sac, and the extraembryonic mesoderm.
What does the extraembryonic mesoderm become?
The extraembryonic mesoderm becomes the extraembryonic sphlanic mesoderm and the extraembryonic somatic mesoderm.
What does the extraembryonic sphlanic mesoderm give rise to?
The extraembryonic sphlanic mesoderm will give rise to the primitive blood which is fetal hemoglobin and blood
What does the extraembryonic somatic mesoderm give rise to?
The extraembryonic somatic mesoderm will give rise to the connecting stalk and the chorion.
What does the epiblast give rise to?
It will give rise to the ectodermal layer of the cells
what is placenta previa?
When the placenta covers the uterine os; very dangerous and can lead to trouble delivering the baby
What is a tubal pregnancy?
A tubal pregnancy is a pregnancy where the embryo implants into the ampulla and the syncithiotrophoblast breaks through the muscular layer of the ampulla and implants
SX: vaginal bleeding for 20+ weeks, never do DIGIT EXAM
