2. development of the nervous system Flashcards
what causes anencephaly
failure of closure of the neural tube at the rostral neuropore
what are the risk factors for a neural tube disorder
epilepsy drugs, previous NTD, diabetes, insufficient folate
name the types of spina bifida
spina bifida occulta
meningocele
menigomyelocele
myeloschisis (spinal cord is open)
what substance is a marker for NTDs
alpha feto protein
what is spina bifida commonly associated with
hydrocephalus
displaced cerrebellum
what does the forebrain develop from
prosencephalon
what does the midbrain develop from
Mesencephalon
what does the hindbrain (cerebellum and brainstem) develop from
Rhombencephalon
describe the development of the forebrain
Grows two lateral expansions
connected to a central slit like space
describe the development of the midbrain
Grows slower than the forebrain
remains as single central tube
describe the development of the hindbrain
Develops into (rest of the) brain stem
and cerebellum with a central ventricle
expanding
what disorders can arise from defective neural crest development (autosomal dominant)
Waardenburg pigment abnormalities deafness heterochromia telecanthus Pax-3 deletion
Treacher Collins TCOF1 gene (treacle) abnormal eye shape hearing loss zygoma malformed ears
what structures do neural crest cells go on to form
skull
sensory and autonomic NS
pigment cells
ganglia adrenal medulla melanocytes connective tissue neurones and glia etc
what are neural crest cells
originally found in the neural plate
during neuralation they leave the neural plate when it becomes a tube
and lie on either side of the tube
neural crest cells then move to the mesoderm
what is the function of the notochord
induces the neural plate by producing chemicals Noggin,
chordin,
follistatin
what is the structure found in the middle of the developing spinal cord
sulcus limitans
what structure is the 4th ventricle opposite
pons
what does the cerebellum develop from
dorsal wall of neural tube
what are two components of the hindbrain/ rhombencephalon
metencephalon (pons and cerebellum)
myelencephalon (medulla)
what structure splits up the basal ganglia into the caudate nucleus and lentiform nucleus
internal capsule
what structures make up the lentiform nucleus
putamen and globus pallidus
where is the fornix
below the corpus callosum
what is the function of the fornix
connects the hippocampus to anterior structures
what structures are related to the third ventricle
diencephalon and thalamus
from what day is a midline groove apparent
19
when do the neuropores close
rostral: 23
caudal: 27
