Embryological Development of the Spinal Cord

Question 1

Steps of neurulation

Answer 1

• Notochord sends signals to induce overlying ectoderm to thicken and form neural plate
  > Neural plate forms from cranial to caudal end
• Neural plate starts folding

Question 2

Dorsal-ventral patterning of neural tube

Answer 2

• Notochord produces Sonic hedgehog (Shh)
• Induces floor plate to produce Shh
• Shh patterns ventral side (basal plate)
• Roof plate produces BMPs
• BMPs pattern dorsal side (alar plate)

Question 3

What do trunk neural crest cells become?

Answer 3

• Sympathetic ganglia
• Adrenal gland
• Sensory neurones (from dorsal root ganglion)
• Melanocytes

Question 4

What do lumbosacral neural crest cells become?

Answer 4

• Parasympathetic neurones
• ENS

Question 5

What do cranial neural crest cells become?

Answer 5

• Sensory CN nuclei
• Parasympathetic ganglia
• Facial skeleton

Question 6

3 primary swellings of brain

Answer 6

• Prosencephalon
• Mesencephalon
• Rhombencephalon

Question 7

What is rachischisis?

Answer 7

Complete inability of neural tube to close

Question 8

What is anencephaly?

Answer 8

Failure of cranial neuropore to close

Question 9

3 types of spina bifida

Answer 9

• Myelomeningocele (meninges and neural tissue)
• Meningocele (meninges)
• Occulta (cyst)