Neurulation and Neural Crest

Question 1

Notochord

Answer 1

mesoderm
extends from primitive node to anterior prechordal plate

distinguishes the Primordial longitudinal axis of the embryo

Template for the vertebral column

Induces the neural plate

Question 2

Nueroectoderm

Answer 2

gives rise to the neural plate
neural groove
neural folds
Neural tube

Question 3

What does the notochord release?

Answer 3

SHH to stimulate the ectoderm to turn to the neural plate

Question 4

Neural tube gives rise to?

Answer 4

CNS
hollow tube
pineal body
posterior part of the pituitary gland

Question 5

Neural crest characteristics

Answer 5

give rise to the PNS
acts like mesoderm by migrating but comes from ectoderm

migrate to head and neck structures and give rise to bone and cartilage and help with the heart

Question 6

Neural Tube closure and Primary neurlation

Answer 6

rostral and caudal neuropore
rostral neuropore close day 25
Caudal neuropore close day28

forming of the brain and spinal cord all the way to the lumbar region of SC

Question 7

Secondary Neurulation

Answer 7

forms sacral and coccyx regions of Nervous system: Caudal Emminence forms on day 20 and round up and connect to primary neurulation and finish at day 42

Question 8

Neural Crest Derivatives

Answer 8

Sensory neurons
spinal ganglia
autonomic ganglia

schwann cells (mylenating cells in PNS)

Meninges (arachna and pia mater)

Melanocytes
melanophores

C-cells of the thyroid

walls of the large arteries of aorta

ciliary muscles
enamel
bone and cartilage of the head and neck

Question 9

Neurocristopathies

Answer 9

Hirschsprungs disease
cleft lip
digeorge
aorticpulmonary septation defects of the heart
anterior defects of the eye
albinism

Question 10

Spinal bifida

Answer 10

failure for the caudal neuropore to close

occulta: closes but is delayed and the vertebral arches are fused, tuft of hair visable
does not affect motor or sensory

Question 11

Meningocele

Answer 11

herniation of the meningies forming a cyst

covered by a membrane
patients may or may not have deficits

Vertebral arches did not form

folate acid helps this

Question 12

Meningomyelocele

Answer 12

both the meningies and the spinal cord are herniated out making a sac
covered by a membrane
will have motor and sensory defects
vertebral arches did not form

folate acid helps this

Question 13

Mylocele or myeloschisis

Answer 13

Caudal neuropore did not fuse at all

major motor and sensory defects

folate acid helps this

Question 14

what is elevated in the Amniotic fluid with spinabifidias and anencephaly

Answer 14

alpha feta protein

Question 15

Anencephaly

Answer 15

failure of the rostral neuropore to close

no close at all
very little brain formation except brain system

Question 16

Encephalocele

Answer 16

failure for the rostral neuropore to close and cause of a protrusion of a membrane that may contain brain tissue or not

Question 17

Meninx primitiva

Answer 17

mesoderm orgin
develops the meninges
derived from cells of the sclerotome
Neural crest cells also migrate in to help

2 kinds: Pachymeninx
Leptomeninges

Question 18

Pachymenix

Answer 18

mesoderm and neural crest and gives rise to the dura mater

Question 19

Leptomeninges

Answer 19

mesoderm and neural crest and gives rise to arachnoid and pia mater

Question 20

mesenchyme

Answer 20

embryonic connective tissue

usually mesoderm and neural crest

Question 21

when does folding of the embryo occur

Answer 21

4th week