Development of the Nervous System: pg 3 & 4 Flashcards
In the _____ week, the surface ectoderm thickens and folds downward to form the nervous system.
3rd
Are these made up from neural tube or neural crest: Lower motor neurons?
Neural tube
Are these made up from neural tube or neural crest: Oligodendrocytes? and what do they do?
Neural tube
They myelinate the axons in the CNS
Are these made up from neural tube or neural crest: Schwann cells? What do they do?
Neural crest
They myelinate and surround all axons in the PNS
Are these made up from neural tube or neural crest: Satellite cells? What do they do?
neural crest
They surround ganglion cells
Are these made up from neural tube or neural crest: astrocytes? What do they do?
Neural tube
Modify the environment, regulates blood flow, forms scar tissue after injury (gliosis)
Are these made up from neural tube or neural crest: Dorsal root ganglion cells?
Neural Crest
Are these made up from neural tube or neural crest: Preganglionic autonomic neurons?
Neural Tube
Are these made up from neural tube or neural crest: Ependymal cells? What do they do?
Neural tube
They line the ventricles of the brain and secrete CSF into the choroid plexus.
Are these made up from neural tube or neural crest: Postganglionic autonomic neurons?
Neural crest
Are these made up from neural tube or neural crest: Upper motor neurons?
Neural Tube
What is an indicator of neural tube defects?
Elevated alpha fetoprotein levels in the amniotic fluid and maternal serum
What is it called where there is a neural tube defect associated with the caudal neuropore?
Spina bifida
What is the most common defect in the vertebral arches?
Spina bifida occulta (10% and usually in L5 or S1 region)
What type of spina bifida cysticas has meninges that project through a vertebral defect forming a sac filled with CSF?
Meningocele
What type of spina bifida cysticas has meninges and spinal cord and roots that project through a vertebral defect forming a sac and is usually in the lumbar or sacral region?
Meningomyelocele
What is the most common of the cysticas?
Meningomyelocele
What type of spina bifida cysticas has an open neural tube lying on the surface of the back and is the most sever type and very rare?
Myeloschisis (rachischisis)
______________ is the failure of the cranial neuropore to close.
Anencephaly
What occurs with anencephaly?
Brain tissue is exposed and the skull fails to form normally. A rudimentary brainstem may be present. This defect results in death.
What is a meningocele?
Meninges herniated into a CSF filled sac.
What is a meningoencephalocele?
Meninges and brain tissue herniated into a sac
What is a meningohydroencephalocele?
Meninges, brain tissue, and ventricles herniated into a sac.
What is it called where there is a displacement of the caudal cerebellar (tonsils) into the foramen magnum, associated with hydrocephalus?
Arnold Chiari malformation
