1. It Takes Teamwork

2. Sperm Anatomy
Acrosome enzymes: hyaluronidase, acrosin, neuraminidase

3. Fertilization and Implantation
Eggs are viable for 72 hours
Sperm is viable for 48 hours
Implantation occurs about
5-6 days after conception

4. Development Week 1
Blastocyst
Inner Cell Mass
(Embryonic Stem Cells)

5. Developmental Week 2 Embryonic Germ Cell Layers: Endoderm Mesoderm
Ectoderm

6. Neural Development (Weeks 3-4)
Neural Plate
Neural Groove
Neural Fold
Neural Crest
Neural Tube

7. Neural Tube Defects
Anencephaly: Failed closure of the Anterior Neuropore
Spina Bifida: Failed closure of the Posterior Neuropore

8. Steps in Neural Development
Mitosis
Migration
Differentiation
Dendritic Sprouting and Bulb Growth
Synaptogenesis
Cell Death
Dendritic Pruning
Myelination

9. Mitosis

10. Migration Growth Cones form and use: Radial Glia Contact Inhibition
Contact Adhesion
Fasciculation
Guide Posts
Chemotropism

11. Growth Cones
Growth Cone

12. Radial Glia Act like scaffolding to assist movement of neurons during
development

13. Contact Inhibition/Adhesion
The growth cones of migrating cells can be attracted to other
cell surfaces by contact adhesion molecules on those cells.
Likewise, growth cones of migrating cells can be repelled from
other cell surfaces by contact inhibition molecules on those cells.

14. Fasciculation Adhesion molecules allow the bonding of same type axons
to form a nerve bundle.

15. Guide Posts Intermediate targets that help guide or
direct the growth cone
of the migrating cell
in the proper direction

16. Chemotropism Target Cell or Tissue
Target tissues or cells can release chemicals that will attract
the specific growth cones of migrating cells.

17. Differentiation

18. Dendritic Sprouting

19. Synaptogenesis

20. Cell Death and Dendritic Pruning

21. Myelination Major growth occurs from birthto 2 years of age
Cephalocaudal Development: from head to toe (tail)
Proximodistal Development: from midline to the periphery
Readiness Principle: Until children reach a state of readiness, they will be unable to perform a task, even with training and practice.