Flashcards in 1.2 Embryology Deck (38):
What is the primitive streak?
Initiates development of germ layers
What function does the notocord have in an adult?
What does the notocord do?
Converts OVERLYING ectoderm to NEUROECTODERM
How does the notocord arise?
What is gastrulation?
formation of the trilaminar embryo
What are the three embryo layers?
What are neuropores?
As the neural tube closes, it zips towards the cranial and caudal end
The openings at either end are neuropores
What does a caudal neural tube defect result in?
What does a cranial neural tube defect result in?
What is spina bifida?
Failure of closure
Where does spina bifida usually occur?
What two features will you see with spina bifida?
What is hydrocephalus?
Accumulation of CSF in the ventricular system
What is anencephaly?
Absence of cranial structures
What is rachischisis caused by?
Failure of neural fold elevation
how would you test for Neural Tube defects?
Raised maternal serum alha-fetoprotein
What can a women consume in order to reduce the possibility of NTDs?
What does most of the neural tube develop into?
What is at the end of the spinal cord?
What happens after the 3rd month, when the spinal cord is the same length of the vertebral column?
The vertebral column keeps extending
Takes nerve roots with it
forms the CAUDA EQUINA
How is the brain first developed?
As three primary brain vesicles
What is the 2nd stage of brain development?
The three primary vesicles develop into 5 secondary brain vesicles
Why does the brain fold up as it develops?
Because it runs out of space linearly
What is the cervical flexure?
The spinal cord-hindbrain junction
What is the cephalic flexure?
What is the role of the ventricles?
Cushion the brain and spinal cord
How is hydrocephalus treated?
Use a shunt
What do the roof and floor plates do in early neural tube development?
Regulate Dorsal and ventral patterning
What does the alar plate do?
What does the basal plate do?
What does the neuroepithelial layer line?
The ventricular system
What is the sulcus limitans?
The junction between the dorsal and ventral halves during early neural tube development
What are the layers of the neural tube in early development? (Inside to out)
Intermediate layer - neuroblasts
Marginal layer - processes
Where are neural crest cells found?
Lateral border of the neuroectoderm tube
What happens to neural crest cells?
Undergo epithelial to mesenchymal transition
What are some neural crest cell derivatives?
Cranial nerve ganglia
Dorsal root ganglia
What is neural crest cell migration particularly susceptible to?