BIOM 3040 TEST 2 QUESTIONS WITH
COMPLETE ANSWERS
what happens if the metaphase plate is perpendicular to the neural tube? - ANSWER
daughter cells migrate back toward outer side of neural tube > another round of DNA
synthesis
what happens if the metaphase plate is parallel to the neural tube? - ANSWER daughter
cells progress to the next stage in neural cell lineage
progenitor cell progression in the CNS - ANSWER multipotential stem cells > bipotential
progenitor cells > neuronal or glial progenitor cells
neuregulin expression - ANSWER marks the proliferating state of neurogenesis and is
rapidly downregulated during differentiation
neuron-glial cell switch - ANSWER cells which instead of becoming neurons become glial
cells, - - downregulation of neuregulin
- secretion of neurogenesis-inhibitory cytokines
- activation of progliogenic transcription factors: SOX-9 and OLIG-2
what are the layers of the early neural tube? - ANSWER ventricular, mantle/intermediate,
marginal layer
,ventricular layer of neural tube - ANSWER gives rise to neuroblasts and glioblasts
mantle/intermediate layer - ANSWER forms the gray matter of the CNS, divided into alar
and basal plates
marginal layer - ANSWER contain axons from neurons in the mantle forming the white
matter
sulcus limitans - ANSWER divides the spinal cord into a dorsal alar plate and a ventral
basal plate
roof plate - ANSWER connects the right and left alar plates dorsally
floor plate - ANSWER connects the right and left basal plates
alar plate - ANSWER dorsal; associated with sensory functions; forms dorsal horn
basal plate - ANSWER ventral; ventral motor roots of spinal nerves; forms ventral horn
what controls segmentation of the spinal cord? - ANSWER segmentation is imposed by
signals from the paraxial medoderm (not from the neural tube itself)
, FGF-8 - ANSWER secreted from the adjacent presomitic mesoderm, causes
undifferentiated neural stem cell in the spinal cord to proliferate
retinoic acid - ANSWER produced by somites in the spinal cord, stimulates stem cells to
differentiate into neurons
flexures - ANSWER prominent forces in shaping the early nervous system: cephalic,
cervical, pontine
Primary vesicles of the brain - ANSWER forebrain (prosencephalon)
midbrain (mesenchepalon)
hindbrain (rhombencephalon)
secondary vesicles of the brain - ANSWER appear at 5 weeksrh
telencephalon
diencephalon
mesencephalon
metencephalon
myelencephalon
telencephalon - ANSWER forms the cerebral hemispheres
COMPLETE ANSWERS
what happens if the metaphase plate is perpendicular to the neural tube? - ANSWER
daughter cells migrate back toward outer side of neural tube > another round of DNA
synthesis
what happens if the metaphase plate is parallel to the neural tube? - ANSWER daughter
cells progress to the next stage in neural cell lineage
progenitor cell progression in the CNS - ANSWER multipotential stem cells > bipotential
progenitor cells > neuronal or glial progenitor cells
neuregulin expression - ANSWER marks the proliferating state of neurogenesis and is
rapidly downregulated during differentiation
neuron-glial cell switch - ANSWER cells which instead of becoming neurons become glial
cells, - - downregulation of neuregulin
- secretion of neurogenesis-inhibitory cytokines
- activation of progliogenic transcription factors: SOX-9 and OLIG-2
what are the layers of the early neural tube? - ANSWER ventricular, mantle/intermediate,
marginal layer
,ventricular layer of neural tube - ANSWER gives rise to neuroblasts and glioblasts
mantle/intermediate layer - ANSWER forms the gray matter of the CNS, divided into alar
and basal plates
marginal layer - ANSWER contain axons from neurons in the mantle forming the white
matter
sulcus limitans - ANSWER divides the spinal cord into a dorsal alar plate and a ventral
basal plate
roof plate - ANSWER connects the right and left alar plates dorsally
floor plate - ANSWER connects the right and left basal plates
alar plate - ANSWER dorsal; associated with sensory functions; forms dorsal horn
basal plate - ANSWER ventral; ventral motor roots of spinal nerves; forms ventral horn
what controls segmentation of the spinal cord? - ANSWER segmentation is imposed by
signals from the paraxial medoderm (not from the neural tube itself)
, FGF-8 - ANSWER secreted from the adjacent presomitic mesoderm, causes
undifferentiated neural stem cell in the spinal cord to proliferate
retinoic acid - ANSWER produced by somites in the spinal cord, stimulates stem cells to
differentiate into neurons
flexures - ANSWER prominent forces in shaping the early nervous system: cephalic,
cervical, pontine
Primary vesicles of the brain - ANSWER forebrain (prosencephalon)
midbrain (mesenchepalon)
hindbrain (rhombencephalon)
secondary vesicles of the brain - ANSWER appear at 5 weeksrh
telencephalon
diencephalon
mesencephalon
metencephalon
myelencephalon
telencephalon - ANSWER forms the cerebral hemispheres
