embryology

Question 1

neural tube

Answer 1

begins w/neural plate
later edges elevate -> neural groove
fuses -> neural tube with cranial and caudal neuropores

Question 2

cranial neuropre

Answer 2

closed day 25

Question 3

caudal neuropore

Answer 3

closed day 27

Question 4

neural crest cells

Answer 4

arise from neuroectomderm as tube is closing

migrate into underlying mesoderm

Question 5

fate of cranial neural crest cells

Answer 5

bones, cartilage, fascia, ligaments, and tendons of face and neck
sensory ganglia, autonomic ganglia

Question 6

fate of spinal neural crest cells

Answer 6

DRGs, autonomic ganglia

heart (fibrous skeleton)

Question 7

shared fate of cranial and spinal neural crest cells

Answer 7

meniges, schwann cells

melanocytes

Question 8

spinal cord

Answer 8

neural tube caudal to 4th pair of somites to form spinal cord

Question 9

layers of neural tube

Answer 9

ventricular, mantle, and marginal

Question 10

ventricular zone in embryo

Answer 10

composed of thick pseudostratifiedd epi called neuroepithelium gives rise to all neurons and glia

Question 11

ventricular zone adult

Answer 11

composed of simple layer of ependymal cells (except a few places in brain)

Question 12

mantle zone

Answer 12

superficial to neuroepi
composed of neuronal cell bodies
alar and basal plates separated by sulcus limitans

Question 13

alar plate

Answer 13

sensory, dorsal horn

Question 14

basal plate

Answer 14

motor, ventral horn

Question 15

marginal zone

Answer 15

outermost layer

composed of nerve processes (axons, dendrites)

Question 16

neuroblasts

Answer 16

derived form neuroepi

from ventral motor horn neurons and dorsal sensory horn neurons

Question 17

gliablasts

Answer 17

derived from neuroepithlium

form astrocytes and oligodendrocytes

Question 18

spinal nn

Answer 18

ventral nerve root + dorsal nerve root
dorsal and ventral rami
dorsal root ganglia are derived from neural crest

Question 19

vesicles

Answer 19

prosencephalon (forebrain)
mesencephalon (midbrain)
rhombencepalon (hindbrain)

Question 20

prosencephalon

Answer 20

telencephalon- cerebral hemis

diencephalon- cranial most portion

Question 21

rhombencephalon

Answer 21

metencephalon

myelencephalon

Question 22

felxures

Answer 22

cervical
cephalic
pontine

Question 23

4th ventricle

Answer 23

lumen of rhombencephalon

Question 24

cerebral aqueduct

Answer 24

lumen of mesencephalon

Question 25

3rd ventricle

Answer 25

lumen of diencephalon

Question 26

lateral ventricles

Answer 26

lumen of telencephalon

Question 27

chorioid plexus

Answer 27

tela choroidea = pia mater +ependymal cells proliferates and invaginates into ventricles develops in roof of 3rd and 4th ventricle and med wall of lateral ventricles

Question 28

brainstem

Answer 28

mesencephalon and rhombencephalon

Question 29

myelencephalon

Answer 29

medulla pontine flexure causes dorsal portion of medulla to be placed laterally associated w/ VIII, IX, X, XII

Question 30

metencephalon

Answer 30

pons marginal layer forms bulk of ponss V, VI ,VII, VIII

Question 31

cerebellum

Answer 31

from metencephalon rhombic lips fuse forming cerebellar plate waves of neruoblasts migrate from alar plate thru marginal layer to form outer cerebellar Cx, making gray matter external

Question 32

pontine flexure

Answer 32

due to rapid development of pons which causes folding

Question 33

mesencephalon

Answer 33

midbrain | III and IV

Question 34

diencephalon

Answer 34

optic vessels, pineal gland, thymus, hypothalmus, pituitary gland optic vesicles epithalamus

Question 35

optic vessesl

Answer 35

primordium of optic n and retina

Question 36

epithalamus

Answer 36

from roofplate contains choriod plexus gives rise to pineal gland

Question 37

thalamus

Answer 37

from superior alar plate swelling of diencephalon buldge into lumen of 3rd ventricle 70-80% of ppl have interthalamic adhesion

Question 38

hypothalamus

Answer 38

from inferior alar plate swelling of diencephalon

Question 39

pitiuitary

Answer 39

neurohypophysis- derived from downgrowth of diencephalon neuroectoderm adenohypophysis- upgrowth of oral ectoderm

Question 40

telencephalon

Answer 40

cerebral hemis and corpus striatum

Question 41

cerebral hemis

Answer 41

2 lateral diverticula of telencephalon waves of neuroblasts migrate thru marginal zone each new wave passes thru older layers youngest cells most superficial final part of fetal life forms gyri and sulci

Question 42

corpus striatum

Answer 42

swelling w/in floor of cerebral hemis

Question 43

spinal tube defects

Answer 43

spina bifida occulta | spina bifida cystic

Question 44

brain neural tube defects

Answer 44

failure to close meroencephaly/anencephaly - no brain craniorachischisis- closure defect extends into spinal cord microcephaly- brain underdevelopment and small cranium

Question 45

encephalocele

Answer 45

defect in skull (often occipital bone) allowing portion of CNS to protrude thru

Question 46

meningocele

Answer 46

only meninges buldge

Question 47

menigoencephalocele

Answer 47

meninges and part of brain buldge

Question 48

meningohyrdoencephalocele

Answer 48

meniges, brain and part of ventricular system buldge

Question 49

congenital hyrdocephalus

Answer 49

increased CSF w/in ventricles resulting in imbalance btwn production and absorption of CSF results in dilation of ventricles proximal to obstruction b/c sutures have not yet fused skull expands thins bones

Question 50

arnold-chiari syndrome

Answer 50

herniation of cerebellar hemis thru foramen magnum, usually due to underdevelopment of post cranial fossa often associates w/spina bifida cystica

Question 51

holoprosencephaly

Answer 51

rare severe anomaly resulting from failure of forebrain neural tube to form cerebral hemis lateral ventricles fuse