The spinal cord arises from the neural tube which forms when the neural plate folds and fuses. The neural tube is made of neuroepithelial cells that migrate and differentiate to form the gray matter of the spinal cord, consisting of the alar plate and basal plate. Axons from cells in the mantle layer collect in the marginal layer to form the white matter. Neural crest cells originate between the neural tube and ectoderm, migrate, and give rise to many structures including ganglion cells, meninges, melanocytes, and Schwann cells.

1. EMBRYOLOGY
By;
RazaRehman, 152
Maria Ilyas, 148
Isfandyar; 156
S p i n a l C o r d

2. Neural Tube
■ Arises from the ectoderm
overlying the notochord
■ Gives rise to the brain and
spinal cord

3. Neural Tube Formation
■ The neural plate folds to
form neural groove with
prominent neural folds
■ The neural folds approach
each other with deepening
of the neural groove

4. Neural Tube Formation
■ The neural folds fuse and a
neural tube is formed
■ The tube, then, separates
from the overlying ectoderm

5. Development of Spinal Cord
Nueroepithilial cells form:
•Ventricular zone
- Ependymal cells
•Intermediate zone
- Form from neuroblasts
•Marginal zone
- Forms white matter

6. Development of the Spinal Cord
■ The cells of the neural tube migrate to form the mantle
layer o f gray matter which differentiates into
Q An alar plate, mostly sensory neurons
Q A basal plate, mostly motor neurons.
Q Separated by sulcuc limitans

7. Development of the Spinal Cord
■ The cells of the mantle layer have axons which
collect in the marginal layer o f white matter

8. Meninges
•Dura mater
-External layer
•Pia arachnoid
- Separated by arachnoid trabeculae
Develop from neural crest cells

9. Neural Crest Cells
■ Originate from cells of
neural folds.
■ Lie between the neural
tube and surface
ectoderm.

10. Neural Crest Cells
■ They, then, migrate to new locations; gives
many derivatives
G A M E S
■ Ganglion cells (DRG, Cranial sensory, Autonomic)
■ Arachnoid and pia maters
■ Melanocytes, Mesenchyme of the pharyngeal arches
■ Enteric ganglia
■ Schwann cells, Suprarenal medulla cells