embryology Flashcards
neural tube
begins w/neural plate
later edges elevate -> neural groove
fuses -> neural tube with cranial and caudal neuropores
cranial neuropre
closed day 25
caudal neuropore
closed day 27
neural crest cells
arise from neuroectomderm as tube is closing
migrate into underlying mesoderm
fate of cranial neural crest cells
bones, cartilage, fascia, ligaments, and tendons of face and neck
sensory ganglia, autonomic ganglia
fate of spinal neural crest cells
DRGs, autonomic ganglia
heart (fibrous skeleton)
shared fate of cranial and spinal neural crest cells
meniges, schwann cells
melanocytes
spinal cord
neural tube caudal to 4th pair of somites to form spinal cord
layers of neural tube
ventricular, mantle, and marginal
ventricular zone in embryo
composed of thick pseudostratifiedd epi called neuroepithelium gives rise to all neurons and glia
ventricular zone adult
composed of simple layer of ependymal cells (except a few places in brain)
mantle zone
superficial to neuroepi
composed of neuronal cell bodies
alar and basal plates separated by sulcus limitans
alar plate
sensory, dorsal horn
basal plate
motor, ventral horn
marginal zone
outermost layer
composed of nerve processes (axons, dendrites)
neuroblasts
derived form neuroepi
from ventral motor horn neurons and dorsal sensory horn neurons
gliablasts
derived from neuroepithlium
form astrocytes and oligodendrocytes
spinal nn
ventral nerve root + dorsal nerve root
dorsal and ventral rami
dorsal root ganglia are derived from neural crest
vesicles
prosencephalon (forebrain)
mesencephalon (midbrain)
rhombencepalon (hindbrain)
prosencephalon
telencephalon- cerebral hemis
diencephalon- cranial most portion