Morphogenesis

Question 1

Name 6 steps of neurolation

Answer 1

1. Neuroplateo develops in mesoderm (18 days)
2. Neural groove forms (20 days)
3. Central canal forms (22 days)
4. Sensory ganglia form (24 days)
5. Closure of anterior & posterior neuropores

Question 2

The central canal forms

Answer 2

Ventricular system

Question 3

Sensory ganglia are derived from

Answer 3

Neural crest cells

Question 4

Which molecule is important for the initiation of neurolation?

Answer 4

BMP

Question 5

What inhibits BMP

Answer 5

Niggin, chordin & folistati

Question 6

Sensory ganglia are derived from

Answer 6

Neural crest cells

Question 7

Which molecule is important for the initiation of neurolation?

Answer 7

BMP

Question 8

Which molecule is important for ventralization?

What produces the molecule?

Answer 8

Sonic Hedgehog

Notocord & floor plate

Question 9

Which molecule is important for dorsalization?

What produces the molecule?

Answer 9

TGF-beta
BMP
Dorsain
Vitamin A

Question 10

What induces floor plate formation?

Answer 10

Notocord

Question 11

Alar plate

(motor or sensory)?

Answer 11

Sensory

Question 12

Basal plate

(motor or sensory)?

Answer 12

Motor

Question 13

Which molecule is responsible for setting rostral-caudal direction?

Answer 13

Retenoic Acid detemines caudal direction

Question 14

Excess external retencacid is

Answer 14

fatal

Question 15

Retinoic acid determines the expression of

Answer 15

HOX genes

Question 16

Derivatives of neural tube (2)

Answer 16

1. All CNS cells

2. Macroglia

Question 17

Horizontal cleavage on precursor neural cells results in 2 cells each containing 1 of 2 molecules, name them

Answer 17

1. Notch

2. Numb

Question 18

Fate of the cell that contains NUMB

Answer 18

Synthesizes NUMB so that it can undergo cleavage again

Question 19

Fate of the cell that contains NOTCH

Answer 19

undergo differentiation
More DELTA: neuroblasts
More NOTCH: glioblasts

Question 20

Describe lateral inhibition as it relates to dividing precursor cells that end up with mor NOTCH

Answer 20

Alternate between neuroblasts and glioblasts

Question 21

Post-mitotic cells migrate from _____ to the ____ and extend axons into ________.

Answer 21

Ventricular zone
Mantle zone
Marginal zone

Question 22

Where are cell bodies during the S phase?

Answer 22

pial surface

Question 23

Where are cell bodies during M phase?

Answer 23

Lumen side/ Neural Tube side

Question 24

Name 3 primary brain vesicles

Answer 24

Prosencephalon
Mesencephalon
Rhombencephalon

Question 25

Name 2 divisions of prosencephalon

Answer 25

Diencephalon & Telencephalon

Question 26

What does the mesencephalon form

Answer 26

Midbrain (still called mesencephalon)

Question 27

Name 3 division of rhombencephalon

Answer 27

Spinal cord myelencephalon metencephalon

Question 28

Pontine flexure seperates

Answer 28

myelencephalon | metencephalon

Question 29

Name embryonic origin | Lateral vesicles

Answer 29

Telencephalon

Question 30

Name embryonic origin | Optic vesicles

Answer 30

Diencephalon

Question 31

Name embryonic origin | Cerebellar aquaduct

Answer 31

Mesencephalon

Question 32

Name embryonic origin | 4th ventricles

Answer 32

Myelencephalon & metencephalon

Question 33

Cephalic flexure separates

Answer 33

Prosencephalon & mesencephalon

Question 34

Failure of the anterior neuropore to close

Answer 34

Anencephaly

Question 35

Failure of the posterior neuropore to close

Answer 35

Spina bifida

Question 36

Abnormal development of midline structures (single brain ventricle, single eye)

Answer 36

Holoprosencephaly

Question 37

Neural Tube completely closed but not encased in mesoderm

Answer 37

spina bifida occulta

Question 38

Meninges and sometimes the spinal cord bulge from the opening where the posterior neuropore should have closed?

Answer 38

Meningocele