click below
click below
Normal Size Small Size show me how
Neuroanatomy unit 1
Term | Definition |
---|---|
Secondary vesicles formed from Prosencephalon | Telencephalon, Diencephalon |
SEcondary vesicles formed from Rhombencephalon | Metencephalon, Myelencephalon |
Craniorachischisis | complete failure of the neural tube closure |
Spinal bifida occulata | 1+ vertebrae fail to close, but overlying skin is closed |
Spinal bifida aperata | protrusion of meninges and/or spinal cord |
meningocele | vertebrae fail to form over defect; defected portion still covered by meninges and skin |
meningomyelocele | herniation of spinal cord and meninges through defect in vertebrae |
Arnold-Chaiari malformation | cerebellum and brainstem are pushed down through foramen magnum; blocks flow of CSF |
anencephaly | ROSTRAL neuropore fails to close (meningocele and spinal bifida = CAUDAL), cerebral hemisphere is absent |
alpha-fetoprotein | a marker in amniotic fluid used to detect neural tube closure |
holoprosencephaly | partial or complete failure of the prosencephalon to separate into the diencephalons |
fetal alcohol syndrome | complete absence of the CORPUS CALLOSUM |
hetertopias | enlarged lateral ventricle --> seizure activity |
lissencephaly | cortical folding almost completely absent due to defective migration of neurons during months 3-4 |
anyotropic lateral sclerosis (LAS) and Polio | degeneration of motor neurons |
tabes dordalis | late stage of syphilis, affect sensory neurons |
parkinson's | dopaminergic neurons are degenerated |
alzheimer's | cholinergic neurons in CNS are degenerated first, then other parts of brain |
Myasthenia gravis | loss of neurotransmitter receptors at postsynaptic membrane |
PNS glia cells | Schwann cells (one per segment), Satellite cells |
CNS glia cells (neuroglia) | oligodendrocytes, astrocytes, ependymal cells, microglial cells |
oligodendrocyte | forms myelin sheath in white matter of CNS; single oligo may wrap dozens of axons |
astrocyte | provides support to neurons |
three types of astrocytes | protoplasmic- part of blood-brain barrier fibrous- repair damaged tissue, may -> scar radial glia- developmental, guide axonal growth and neuronal migration |
Microglia | respond to CNS injury, transform to macrophages |
ependymal cells | form lining of ventricles |
Multiple Sclerosis | demyelinating disease in CNS that interfere with motor and sensory, oligodendrocytes are destroyed gradually |
Guillan-Barre | axonal demyelination in PNS |
derivation of brain tumors | glia cells |
Supporting tissues in PNS | epineurium- continues with dura mater perineurium endoneurium- surround each schwann cell |