Bio467 Exam 2 – Neurodevelopment
Questions & Answers
Pattern formation - AnswersThe process by which groups of cells adopt distinct fates
during development
Commitment - AnswersThe restriction of a cell's developmental fate - subtle, involves
changes in gene expression
Differentiation - AnswersThe generation of a specialized cell type from committed
precursors - changes in functional/morphological features
Gastrulation - Answersthe transformation of the blastula (early sheet of ES cells) to
produce the 3 germ layers
What are the 3 germ layers that derive from the epiblast? (outer to inner) -
AnswersEctoderm, mesoderm, endoderm
Which germ layer generates the nervous system? - AnswersEctoderm
What is neurulation? - AnswersTransformation of a region of the ectoderm into the
neural tube/plate
Describe neural tube closure. - Answers- Neural plate folds in and fuses at the dorsal lip
to form the neural tube
- Neural tube generates a neuroepithelium (makes the CNS)
- Dorsal lip of the neural tube generates the neural crest (makes the PNS)
What is anencephaly? - AnswersRostral neural tube closure defect - leads to deformity
in which some or all of fetal brain is missing
What is spina bifida? - AnswersCaudal neural tube closure defect - defects in the
lumbar spinal column caused by imperfect union of vertebral parts
Role of folates in neural tube closure? - AnswersStudies suggest it promotes neural
tube closure - folate fortification is associated with significant decreases in NTDs
What is EMT (epithelial-mesenchymal transition)? - AnswersProcess where stem cells
in dorsal lip of neural tube transform into migratory neural crest
What is neurogenesis? - Answersformation of new neurons from neural stem cells
, What is gliogenesis? - Answersformation of peripheral glia from neurons
Example of cells formed by gliogenesis? - AnswersSchwann cells, astrocytes,
oligodendrocytes, ependymal cells
What forms the CNS? - Answersneural tube
What forms the PNS? - Answersneural crest
How does the neural tube turn into the spinal cord? - AnswersAfter neural tube closure,
dividing neuroepithelial progenitors (NEPs) surround the central canal (future ventricular
system) in the ventricular zone (VZ)
Describe neuroepithelial progenitor (NEP) proliferation. - Answers- NEP has a small
process at the pill and ventricular surface of the ventricular zone
- NEP soma move along this process - known as inter kinetic nuclear migration
- Mitosis occurs when soma is at the ventricular surface
What generates radial glia? - AnswersNEPs
Where are radial glia found? - AnswersDeveloping CNS
Function of radial glia? - AnswersDirect neurogenesis by supporting/guiding migrating
neurons
Immature neurons divide from ___ in the ventricular zone. Immature neurons utilize ___
along radial glia fibers. - AnswersRadial glia, radial migration
How is the dorso-ventral axis of the spinal cord patterned? - Answers- Neural progenitor
progeny migrate outward radially from the ventricular zone into the mantle zone AKA
progenitor domain. Migration is guided by radial glia
- Sensory neurons arise in dorsal domains near roofplate
- Motor neurons arise in ventral domains near floor plate and notochord
Role of notochord in neurulation - AnswersThe notochord ventralizes the neural tube
Effect of implanting an extra notochord in the neural tube? - AnswersConverts the
lateral neural tube into more ventral state
What is a morphogen? - AnswersSignaling molecules that elicit concentration-
dependent changes in cell behavior
What do morphogen gradients regulate? - AnswersActivity/expression of specific
transcription factors, which mediate differential gene expression (changes in
commitment and differentiation)
Questions & Answers
Pattern formation - AnswersThe process by which groups of cells adopt distinct fates
during development
Commitment - AnswersThe restriction of a cell's developmental fate - subtle, involves
changes in gene expression
Differentiation - AnswersThe generation of a specialized cell type from committed
precursors - changes in functional/morphological features
Gastrulation - Answersthe transformation of the blastula (early sheet of ES cells) to
produce the 3 germ layers
What are the 3 germ layers that derive from the epiblast? (outer to inner) -
AnswersEctoderm, mesoderm, endoderm
Which germ layer generates the nervous system? - AnswersEctoderm
What is neurulation? - AnswersTransformation of a region of the ectoderm into the
neural tube/plate
Describe neural tube closure. - Answers- Neural plate folds in and fuses at the dorsal lip
to form the neural tube
- Neural tube generates a neuroepithelium (makes the CNS)
- Dorsal lip of the neural tube generates the neural crest (makes the PNS)
What is anencephaly? - AnswersRostral neural tube closure defect - leads to deformity
in which some or all of fetal brain is missing
What is spina bifida? - AnswersCaudal neural tube closure defect - defects in the
lumbar spinal column caused by imperfect union of vertebral parts
Role of folates in neural tube closure? - AnswersStudies suggest it promotes neural
tube closure - folate fortification is associated with significant decreases in NTDs
What is EMT (epithelial-mesenchymal transition)? - AnswersProcess where stem cells
in dorsal lip of neural tube transform into migratory neural crest
What is neurogenesis? - Answersformation of new neurons from neural stem cells
, What is gliogenesis? - Answersformation of peripheral glia from neurons
Example of cells formed by gliogenesis? - AnswersSchwann cells, astrocytes,
oligodendrocytes, ependymal cells
What forms the CNS? - Answersneural tube
What forms the PNS? - Answersneural crest
How does the neural tube turn into the spinal cord? - AnswersAfter neural tube closure,
dividing neuroepithelial progenitors (NEPs) surround the central canal (future ventricular
system) in the ventricular zone (VZ)
Describe neuroepithelial progenitor (NEP) proliferation. - Answers- NEP has a small
process at the pill and ventricular surface of the ventricular zone
- NEP soma move along this process - known as inter kinetic nuclear migration
- Mitosis occurs when soma is at the ventricular surface
What generates radial glia? - AnswersNEPs
Where are radial glia found? - AnswersDeveloping CNS
Function of radial glia? - AnswersDirect neurogenesis by supporting/guiding migrating
neurons
Immature neurons divide from ___ in the ventricular zone. Immature neurons utilize ___
along radial glia fibers. - AnswersRadial glia, radial migration
How is the dorso-ventral axis of the spinal cord patterned? - Answers- Neural progenitor
progeny migrate outward radially from the ventricular zone into the mantle zone AKA
progenitor domain. Migration is guided by radial glia
- Sensory neurons arise in dorsal domains near roofplate
- Motor neurons arise in ventral domains near floor plate and notochord
Role of notochord in neurulation - AnswersThe notochord ventralizes the neural tube
Effect of implanting an extra notochord in the neural tube? - AnswersConverts the
lateral neural tube into more ventral state
What is a morphogen? - AnswersSignaling molecules that elicit concentration-
dependent changes in cell behavior
What do morphogen gradients regulate? - AnswersActivity/expression of specific
transcription factors, which mediate differential gene expression (changes in
commitment and differentiation)
