embryology Flashcards
when does CNS start development
week 3
how is neural tube formed
neural folds migrate towards each other and fuse in the midline forming neural tube. Anterior and posterior ends stay open to allow communication with amniotic fluid
spinal bifida occulata
spinal cord not effected
what should women take during child bearing age to reduce neural tube deficiencies
folic acid supplements- decreases neural tube defects
three flexures during folding of CNS
cephalic, cervical and pontine
why do we have folds in the brain
saves space so during birth its easier and the smaller the brain the easier it is to pass information between different areas
lissencephaly- very rare condition
brain remains smooth- seizures, abnormal muscle tone, failure to thrive
wheat forms the ventricular system
the lumen of the neural tube
when does CSF develop
week 5 and produced by choroid plexus
drains into subarachnoid space via openings in the 4th ventricle and then drains into venous system
Where does PNS develop from
neural crest cells
what happens if pharyngeal clefts don’t obliterate
brachial cysts can develop in adulthood
what does the 1st pharyngeal cleft give rise too
external auditory meatus
what comprises 1st pharyngeal arch
maxillary and mandibular prominence
what comprises 2nd pharyngeal arch
stapedial artery and hyoid artery
what comprises 3rd pharyngeal arch
common carotid artery and associated with glossopharyngeal artery
