Neuroembryology - Development Of The Nervous System

Front 1

at what point in embryology does the neural plate form

Back 1

week 3

Front 2

what is primary neurulation

Back 2

formation of the neural tube

Front 3

what is secondary neurulation

Back 3

closing of the neural pores; occurs the 23rd and 25th day

Front 4

which closes first, the rostral or caudal end of neural tube?

Back 4

rostral(23 vs 25 day)

Front 5

what is craniorachischisis

Back 5

failure of the rostral neural tube to close and is fatal

Front 6

what results from failure of the rostral nenural pore to close?

Back 6

anencephaly or meroanencephaly

Front 7

what is the result of a failure of the caudal neuropore to close?

Back 7

spina bifida

Front 8

spina bifida occulta

Back 8

fairly common (10%); malformation of some vertebrae that dont completely close in the cauda regions, but no neurological deformities

Front 9

spina bifida cystica

Back 9

serious vertebral and cauda deformity involving neurological complications

Front 10

rachischisis

Back 10

failure of caudal neural tube to close; tube can be found within enlarged subarachnoid space or continuous with ectoderm

Front 11

arnold chiari malformation (type 2)

Back 11

rachischisis in which the caudal end of spinal cord is tethered to skin and, during development, brain and cerebellum are pulled into foramen magnum; hydrocephaly occurs in which verntricles are filled with CSF that cannot escape

Front 12

how do you screen for fetal neural tube closure defects

Back 12

test for maternal serum alphafetoprotein

Front 13

what can be used in pregnant women to prevent neural tube defects?

Back 13

folic acid will prevent most of these defects.

Front 14

sulcus limitans

Back 14

longitudinal division of neual tube that divides neurons destins to become sensory(dorsal) from motor and interneurons (ventral)

Front 15

SHHs and BMPs

Back 15

differentiation and patterning proteins produced in opposign concentrations to help differentiate neurons and limit differentiation potential.

Front 16

ventricular zone of neural tube

Back 16

ependymal cells that line the ventricles and central canal

Front 17

intermediate zone of neural tube

Back 17

gray matter; proliferating neurons form new neurons from subventricular zone and migrate out, even al the way to cerebral cortex.

Front 18

marginal zone

Back 18

white matter

Front 19

what structures coem from neural crest cells?

Back 19

1) DRGs
2) skin pigment cells
3)schwanns
4)adrenal medulla
5)preganglionic autonomics

Front 20

what are placodes and what do they form?

Back 20

they are neural crest-like cells coming off epithelium overlying neural tube and neural structures. They give rise to eye lenses, hair cells of the inner ear, olfactory epithelium, and parts or all of ganglia of CN V, VII, VIII, IX, X

Front 21

somites

Back 21

lie lateral to neural tube and give rise to:
1)sclerotome
2)myotome
3)dermatome

Front 22

3 primary vesicles give rise to brain

Back 22

1)prosencephalon --> beomes telencephalon and diencephalon
2)mesencephalon
3)rhombencephalon --> metencephalon and myencephalon

Front 23

what are the two initial flexures or bends?

Back 23

mesencephalic flexure --> persists to adulthood
cervical flexure --. transient

Front 24

telencephalon

Back 24

cerebrum, corpus striatum, lateral ventricles

Front 25

diencephalon

Back 25

thalamus, optic cup, hypothalamus, etc., third ventricle

Front 26

mesencephalon

Back 26

midbrain, cerebral aqueduct

Front 27

metencephalon

Back 27

pons and cerebellum, rostral forth ventricle

Front 28

myelencephalon

Back 28

medulla, caudal forth ventricle, part of central canal

Front 29

when are the primary vesicles complete

Back 29

end of fourth week

Front 30

when are the 5 brain vesicles complete

Back 30

fifth week

Front 31

pontine flexure

Back 31

6th week; forms pons and choroid plexus; the alar plate is deflected laterally in this region; rostral edges form cerebellum and 4th ventricle

Front 32

corpus striatum

Back 32

teh telencephalic area immediately adjacent to diencephalon which become basal ganglia

Front 33

lamina terminalis

Back 33

6th week, connects two halves of brain; provides framework for formation of corpus callosum and anterior commissure

Front 34

rathke's pouch

Back 34

outgrowth from roof of mouth that forms adenohypophysis

Front 35

lissencephaly

Back 35

outer cortex is smooth; due either to defective neuron migration in 3-4th month or neurons being insufficiently mamde in subventricular zone

Front 36

heteroptopias

Back 36

gray matter displaced because didnt migrate to cortex; seizures

Front 37

myelination

Back 37

from birth to 2 years of age continuous and correlates with control of hands and feet