BCN Chapter 24 Flashcards
What is the order for neural development in the CNS?
Ectoderm –>
Neuro Plate –>
Neural fold –>
Neural Tube (Begins in cervical region anterior portion first then posterior) –>
Neural Crest (arise from lateral margin of neural fold)
What does the Prosencephalon become?
1a. Telencephalon (outer cortex)
1b. Diencephalon
(both for secondary and mature)
What does the Mesencephalon become?
Secondary
2a. Mesencephalon
Mature
2aa. Midbrain
What does the Rhombencephalon become?
Secondary
3a. Metencephalon (this goes to cerebellum in mature)
3b. Myelencephalon (this goes to medulla in mature)
Mature
3ab. Cerebellum
3ba. Medulla
What are the 3 layers in the neural tube as cell division occurs?
Ventricular layer - cell division occurs (mitosis)
Mantle zone (DNA synthesis)
Marginal layer - farthest from lumen
What are the first cells to migrate away from ventricular zone into the mantle layer?
Neuroblasts
What type of cell differentiates into astrocytes and oligodendrocytes and where does this happen?
Glioblasts
Happens in the mantle and marginal layers
Where are Epenymal cells generated?
In the ventricular layer (line future ventricles)
What is the difference between the Alar and Basal plates?
Alar - Sensory (dorsal)
Basal - Motor (ventral)
What is axonal growth and path finding guided by?
Molecular signals on cell surface or extra cellular matrix
- Chemoattractants
- Chemorepellants
When does myelination of the CNS axons begin?
16th week of gestation and continues till 3 years old
What is synaptogenesis?
Formation of synapses between neurons and nervous system.
What is Apoptosis and why does it occur?
Programmed cell death
Nervous system over develops (too many neurons)
Poorly connected neurons are eliminated (about half of the total)
What are the types of spina bifida?
Meningocele - sac contains CSF
Meningomyelocele - contains neural tissue
How can a significant portion of neural tube defects be prevented?
Maternal use of folic acid