Nervous System Embryology Flashcards
What do cells from the primitive streak become?
Descend to become the mesoderm
What do cells from the primitive node become?
The notochord
What is the role of the notochord?
Sends growth factors to the ectoderm above to differentiate ectoderm cells into neuroectodermal cells
What is the neuroplate?
The rapidly proliferating neuroectodermal cells
What do the neuroplate cells form?
They grow down forming the neural grooves and neural folds (on the edge)
What occurs once the neural grooves close?
They form the neural tube and pinch off the neural crest cells
What somite is helpful for differentiating between brain and spinal cord?
Superior to the 4th is brain
Inferior to the 4th is spinal cord
What are the three layers of the neural tube caudal to the 4th somite?
Ventricular Zone: lines neurotube
Marginal Zone
Intermediate Zone: formed by neuroblasts from ventricular layer
What comes from the ventricular zone?
Grey matter and ALL neural cells
What comes from the marginal zone?
White matter
What comes from the Alar plate?
Sensory neurons
What comes from the Basal plate?
Motor neurons
What is the sulcus limitans?
Separation of the Alar and Basal plates
What are the floor and roof plates?
Where axons cross-over
What do the pia and arachnoid mater come from?
Neural crest cells and mesenchyme
