Intro
During what weeks are the organ systems developing simultaneously?
Weeks 3-8; also called the embryonic period
false it is only a germ layer
What genes cause the sclerotome to express PAX1? What happens when PAX1 is expressed?
Shh and noggin; helps vertebrae formation
What forms the urogenital system?
intermediate mesoderm
What do astrocytes come from?
Neuroectoderm
Which folding progresses due to growth of CNA and the amnion?
Craniocaudal folding
The paraxial mesoderm becomes ....
bone, muscle, subcutaneous tissue
What two genes cause the ventromedial somite to form the sclerotome
Shh and noggin
The appendicular skeleton arises from what mesoderm derivatives?
Lateral plate mesoderm
Failure or late closure of posterior neural tube causes
spinal bifida
What gene regulates basic segmentation of human embryo in the craniocaudal direction?
Hox genes
Which somitomeres contribute to pharyngeal arches?
1-7
Which proteins activate PAX3 genes?
Wnt; they activate PAX 3 gene to demarcate dermatome between developing muscle precursors
The lateral plate divides into 2 layers- what are they and what do they do?
Somatic: appendicular skeleton
Splanchnic: hollow viscera smooth muscle (splanchnic)
You see a child with these phenotypical features: short palpebral fissures, railroad track ears, mild ptosis, fleshy lips, prominent epicentral folds. What syndrome?
Fetal alcohol syndrome
What 2 structures form the umbilical cord?
Yolk stalk and connecting stalk
Which embryological structure drives much of the mesoderm development including somites?
notochord
What 2 genes block BMP
noggin and chordin
What receptors does the ectoderm express?
BMP and TGF-B
Which germ layer forms red blood cells, white blood cells, and microglia?
mesoderm
What is initially the most cranial structure in the embryo?
Cardiogenic area
What cells migrate to form the dermis of the back?
Dermatomce cells that become mesenchymal migrate beneath the ectoderm to form dermis
Interplay between these genes is integral to differentiating remaining epiblast tissue into the ectoderm
BMP and HOX genes
If you see a histology slide of the epidermis, what germ layer will you say its derived from?
ectoderm
Which cranial nerves are associated with ectoderm?
CN VIII and CN I