Neuro

Question 1

notochord

Answer 1

induces the overlying ectoderm to differentiate into neuroectoderm and form the neural plate

the notochord eventually becomes the nucleus purposes of the intervertebral disc in adults

Question 2

neural plate

Answer 2

gives rise to the neural tube and neural crest cells

Question 3

rostral part of neural tube

caudal part

Answer 3

becomes the adult brain

spinal chord

Question 4

surface ectoderm

Answer 4

adenopypophysis (rathke pouch), lens of the eye, epithelial linings of the oral cavity, sensory organs of the dear and olfactor epithelium
epidermus, anal canal below the pectinate line
parotid, sweat and mammary glands

Question 5

neuroectoderm (which gives rise to the neural plate –> neural tube and neural crest cells)

Answer 5

Think CNS
Brain (neurohypophysis, CNS neurons, oligodendrocytes, astrocytes, ependymal cells, pineal gland), retina and optic nerve, spinal chord (caudal neural tube)

Question 6

Neural crest derivatives

Answer 6

PNS!!!
-dorsal root ganglia, cranial nerves (not optic), celiac ganglion, schwann cells, ANS).

funny ones:
melanocytes, chromaffin cells of adrenal medulla, parafollicular C cells of thyroid, pia and arachnoid, bones of the skull, odontoblasts and

dont forget - aorticopulmonary septum

Question 7

Forebrain (prosencephalon) –>

Answer 7

telencephalon –> cerebral hemispheres (walls) and lateral ventricles (cavities)

diancephalon –> thalamus and third ventricle

Question 8

Midbrain (mesencephalon) –>

Answer 8

Mesencephalon (secondary vessicle) –> midbrain and aqueduct

Question 9

Hindbrain (rhombencephalon) –>

Answer 9

Metencephalon –> pons and upper fourth ventricle
and the cerebellum

myelencephalon –> medulla and lower part of the fourth ventricle

Question 10

neuro related mesoderm derivative

Answer 10

microglia (like macrophages originate from the mesoderm)

Question 11

neural tube defects general

Answer 11

• neuroporse fail to fuse at week 4
• assoc. with low folate
• elevated a-fetoprotein (AFP) in amniotic fluid and maternal serum.
• increased acetylcholinesterase in amniotic fluid because fetal ACeE in CSF transudates across defect into the amniotic fluid)

Question 12

spina bifida occulta

Answer 12

• failure of the BONY spinal canal to close, but no herniation
• usually lower vertebral
• dura is intact
• assoc with tuft of hair or skin dimple

Question 13

meningocele

Answer 13

meninges (but not the spinal cord) herniate through the spinal canal defect, normal AFP

Question 14

meningomyelocele

Answer 14

meninges and the spinal cord herniate through the spinal canal defect

Question 15

anecephaly

Answer 15

• forebrain anomaly
• malformation of anterior neural tube results in no forebrain
• open calvarium
• increased AFP, polyhydramnios (no swallowing center in brain)
• assoc with DM 1
• give folate to reduce risk

Question 16

polyhydraminos

Answer 16

excess amniotic fluid in sac…. rememeber baby swallows amniotic fluid

Question 17

holoprosencephaly

Answer 17

failure of the L and R hemispheres to separate
-week 5-6
complex etiology but most likely mutations in sonic hedgehog signalling pathway
clinical: cleft lip/palate
most severe: cyclopia

Question 18

Chiari II (anold-chiari malformation)

Answer 18

• herniation of cerebellar tonsils and vermis through foremen magnum
• with aqueductal stenosis and hydrocephalus.
• myelomeningocele may be present and paralysis below the defect

Question 19

Dandy-walker

Answer 19

agenesis of cerebellar vermis with cystic enlargement of 4th ventricle (fills the enlarged posterior fossa). Assoc with hydrocephalus and spina bifida

Question 20

syringomyelia

Answer 20

• cystic cavity within the spinal chord (neck)
• crossing anterior spinal commissural fibers are typically damaged first.
• cape like bilateral loss of pain and temperature in upper extremities
• fine touch is preserved
• C8-T1
• assoc with Chiari I

Question 21

Chiari 1

Answer 21

> 3-5 mm cerebellar tonsillar ectopia

• congenital
• usually asymptotic in childhood
• manifests with headaches and cerebellar symptoms

Question 22

Tongue muscles are derived from?

Answer 22

occipital myotomes

Question 23

Motor innervation of tongue?

Answer 23

CNXII

Question 24

Taste of tongue CN?

Answer 24

CN VII anterior 2/3
IX posterior 1/3
and X (solitary) very back back

Question 25

Pain tongue

Answer 25

CN V3 anterior 2/3
IX posterior 1/3
X(solitary) at the very back

Question 26

branchial arches for the anterior 2/3 of tongue?

Answer 26

1 and 2nd branchial arches

Question 27

branchial arches for the posterior 1/3 of tongue?

Answer 27

3rd and 4th branchial arges