Development of Nervous System Flashcards
Where does the nervous system and notochord originate form?
nervous system - ectoderm
notochord - mesoderm
What are the five vesicles?
Telencephalon Diencephalon Midbrain Metencephalon Myelencephalon
Neural Crest cells
PNS cranial nerve sensory ganglion cells dorsal root ganglion cells postganglionic autonomic ganglion cells chromaffin cells of the adrenal medulla Schwann cells melanocytes
3 layers of neural tube
Ventricular (innermost)
mantle (gray)
marginal (white)
midpoint of neural canal
Sulcus Limitans
Where do neurocytes migrate in the developing spinal cord
Dorsal = Alar plate = sensory Ventral = Basal plate = motor Intermediate = autonomics = lateral horn
Which foramen are associated with the 4th ventricle?
Foramen of Luschka (lateral)
Foramen of Magendie (medial)
Where is CSF made?
Choroid Plexus (thickening of pia)
Parts of the Pons
Dorsal - tegmentum
Ventral - basilar
What does the metencephalon form?
Pons & cerebellum
What does myelencephalon become?
Medulla
What does mesencephalon become?
Midbrain
Parts of the midbrain?
tementum (continuation medially)
tectal (dorsal)
peduncular (ventral) (crus cerebri)
What does diencephalon become?
thalamus (dorsal) hypothalamus (ventral) Pineal Choroid plexus optic vessicles
What does telencephalon become?
cerebral hemisphere, basal ganglia, hippocampus, amygdala
Spina Bifida (myeloschisis)
not fully closed vertebra
Spina Bifida cystica (two types)
meningocele - CSF is sticking out
meningomyocele - neural tube outside of body
Rachischisis
problem with neural tube formation
Meningocele
CSF herniation
Meningoencephalocele
brain tissue & CSF
Meningohydroencephalocele
ventricles & brain tissue & CSF
Arnold-chiari
caudal displacement of posterior cranial fossa structures (cerebellum) through foramen magnum
Microcephaly
cranial vault smaller than normal
Dandy-walkery syndrome
phenotype: dramatic or imperceptible 4th ventricle enlargement medial and lateral apertures not found absence of cerebellar vermis cysts form on internal base of skull
Hydrocephaly
accumulation of CSF
usually blockage of cerebral aqueduct
Anencephaly
missing cranial vault
brain usually necrotized
Craniorachischisis
issue with brain and spinal cord
