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Clinical Neuroscience weeks 1-3 > CNS Embryo > Flashcards

Flashcards in CNS Embryo Deck (32):
1

Brain Development begins when?

3rd week of gestation

2

What is the first event in brain development

Formation of neural tube and neural crest cells

3

Brain develops from which of the three germ layers

Ectoderm...brain is just fancy skin

4

Brain develops into three vesicles at how many weeks gestation

4 (Prosencephalon, Mesencephalon, Rhombencephalon)

5

Brain develops into 5 vesicles at how many weeks gestation

5

6

Neural plate formed when

Week 3

7

Neural Tube formed what week

week 4

8

Cerebral hemispheres enlarge when

week 8

9

Neuroblasts form what>

All neurons in the CNS

10

Neuroblasts differentiate from

Neuroepithelial cells

11

Glioblasts form what?

Radial glial cells, astrocytes, oligodendrocytes, ependymocytes, tanycyctes, choroid plexus cells

12

What are radial glial cells

They serve as guide wires for the migration of neurons. Neurons attach to and travel along the radial glial cells to their final destination

13

What is the sulcus limitans?

Separates the alar plate (Dorsal Sensory neurons) from the basal plate (ventral motor neurons). This remains a useful anatomical marker in the adult brainstem

14

Neurogenesis in the alar plate forms what

sensory neurons and nuclei of the spinal cord and brain stem

15

Dorsal root ganglia neurons are derived from which plate?

Alar

16

Neurogenesis in the basal plate

Motor neurons and nuclei of the spinal cord and brain stem

17

Which elongates faster, spinal column or spinal cord?

Column....this accounts for the rostral migration of the end of the spinal cord (or the conus medullaris) during fetal development.

18

Adult spinal cord ends where?

L1-2

19

3 month fetus= spinal cord ending where?

endo of spinal column

20

6 mos fetus = spinal cord ending where?

S1

21

9 mos fetus = conus medullaris where?

L3

22

Failure of the Anterior Neural pore to close=

Anencephaly and Encephalocele

23

Failure of the posterior neural pore to close =

Spina Bifida
Meningocele
Myelomeningocele

24

Neural tube closure defects are closely associated with what

Folic acid deficiency in the mother....
Folic acid supplements takes early in pregnancy, especially during the first few weeks of gestation significantly reduce the incidence of neural tube closure defects

25

Failure of neural tube closure allows alpha-fetal protein to leak out into the amniotic fluid and into the bloodstream of the mother. Testing for alpha-fetal protein levels in the mother's blood or via amniocentesis can reveal neural tube defects

ok

26

SPO

Spina Bifida Occulta.....failure of mesodermal cells to form bony dorsal vertebrae that surrounds the spinal cord...these individuals rarely develop neurological symptoms

27

SPO clinical symptoms

tuft of hair over the lumbar sacral area

28

SPA

Spina Bifida Aperta

SPA with Meningocele, the meninges extend into the outpouching

SPA with myelomeningocele, meninges, spinal cord and filum terminale extend into the outpouching

29

Chiari malformation

displacement of the cerebellar tonsils below the foramen magnum.

30

Neuroblasts and Glioblasts are generated where

in the ventricular zone

31

Ventricular zone neuroepithelial cells differentiate into neuroblasts and glioblasts...

Neuroblasts then form all neurons. Glioblasts form glial cells

32

Microglia arise from ...

monocytes in the circulation and invade the CNS during the third week with the formation of cerebral blood vessels.