Neuroembryology

Question 1

from what cell layer does the CNS arise?

Answer 1

ectoderm

Question 2

from what cell layer does the notochord arise?

Answer 2

mesoderm

Question 3

what does the notochord induce the ectoderm to differentiate into?

Answer 3

neural crest cells

neural plate

Question 4

when does neurulation begin

Answer 4

week 3

Question 5

what is the adult remnant of the notochord?

Answer 5

nucleus pulposus

Question 6

what are are developmental stages of the neural plate and what induces these changes

Answer 6

neural plate => neural groove => neural tube

INDUCED BY NOTOCORD

Question 7

from what structure does most of the CNS arise

Answer 7

neural tube

Question 8

from what structure does most of the PNS arise

Answer 8

neural crest

Question 9

where does the spinal cord develop

Answer 9

caudal to the fourth pair of somites

Question 10

what is spina bifida

Answer 10

failure of one or more neural folds to fuse

Question 11

what is it called when there is an unfused neural arch but skin remains intact

Answer 11

spina bifida occulta

Question 12

what is the difference btwn meningocele and meningomyelocele

Answer 12

in BOTH, meninges protrude through unfused arch

in meningomyelocele ONLY, neural tissue also protrudes

Question 13

what is myeloschisis?

Answer 13

when neural tissue is open to external environment

Question 14

what are the three primary vesicles

Answer 14

forebrain
midbrain
hindbrain

Question 15

what are the five secondary vesicles

Answer 15

telencephalon
diencephalon
mesencephalon
metencephalon
myelencephalon

Question 16

what secondary vesicles does the forebrain become

Answer 16

telencephalon

diencephalon

Question 17

what secondary vesicles does the midbrain become

Answer 17

does not divide - remains midbrain AKA mesencephaln

Question 18

what secondary vesicles does the hindbrain become

Answer 18

metencephalon

myelencephalon

Question 19

what structures does the telencephalon develop into

Answer 19

wall: cerebral hemispheres
cavity: lateral ventricles

Question 20

what structures does the diencephalon develop into

Answer 20

wall: thalamus (hypo, epi, para)
cavity: 3rd ventricle

Question 21

what structures does the mesencephalon develop into

Answer 21

wall: midbrain
cavity: aqueduct

Question 22

what structures does the metencephalon develop into

Answer 22

wall: pons and cerebellum
cavity: upper fourth ventricle

Question 23

what structures does the myelencephalon develop into

Answer 23

wall: medulla
cavity: lower fourth ventricle

Question 24

when does the brain bend?

Answer 24

week 5

Question 25

what are the three flexures, from superior to inferior?

Answer 25

midbrain/mesencephalic pontine cervical

Question 26

which flexure separates the medbrain from the forebrain

Answer 26

cephalic flexure

Question 27

which flexure separates the spinal column from the hindbrain

Answer 27

cervical flexure

Question 28

which flexure separates the myelencephalon and metencephalon

Answer 28

pontine flexure

Question 29

in what secondary structure does migration of alar plate neuroblasts occur

Answer 29

myelencephalon

Question 30

what do the alar plates give rise to

Answer 30

sensory nuclei

Question 31

what do the basal plates give rise to

Answer 31

motor nuclei

Question 32

from what structure of the metencephalon does the cerebellum arise

Answer 32

cerebellar swellings of the dorsal alar plate

Question 33

what structure is overgrown in the development of the cerebellum

Answer 33

the 4th ventricle

Question 34

what embryonic structure gives rise to the choroid plexus

Answer 34

tela chordea

Question 35

where does the thalamus develop

Answer 35

on each side of the third ventricle | usually fuses at midline

Question 36

from what structure does the pineal gland develop

Answer 36

from the caudal part of the roof of the diencephalon

Question 37

when do optic vesicles appear

Answer 37

as the rostral neuropore is closing

Question 38

where does the choroid plexus develop

Answer 38

from the tela chordiae at medial wall of the cerebral hemisphere

Question 39

mesenchyme trapped in the fissure between the cerebral hemispheres as they expand becomes what?

Answer 39

falx cerebri