MCB 461 - Exam 3 || 100% Correct Solutions.
Brain development begins as a correct answers tube (neural tube)
neural plate correct answers thickened region of the ectodermal layer that gives rise to the neural
tube. It is where progenitors for nervous system arise
2 molecular mechanisms of neural induction correct answers 1. BMP in ventral ectoderm
prevents neural induction and promotes epidermis formation
2. BMP inhibitors (Noggin, Chordin, Follistatin) induce neural tissue/plate in dorsal ectoderm
Once neurons are born, they migrate towards ______ of neural tube correct answers outskirts
_______ genes control regional identity and are expressed in different regions of AP axis and
DV axis correct answers homeobox (hox)
How do some cells in neuroectoderm become neuroblasts? correct answers 1. Proneural clusters
2. Lateral inhibition
Proneural clusters correct answers Clusters of cells that initiate neural fate
Lateral Inhibition correct answers Cells within proneural cluster interact to decide which cells
will become neuron
proneural genes correct answers - cause cells within proneural clusters to initiate a neural rather
than epidermal cell fate
- basic helix-loop-helix TFs
- equally expressed in cells w/in clusters
neurogenic genes encode __________ genes important for communication mechanisms that
mediate ___________ correct answers Notch signaling pathway (Notch, Delta, Suppressor of
Hairless); lateral inhibition
Notch signaling pathway activates bHLH TFs, like E(spl)-C, that functions in: correct answers
inhibiting proneural genes and neurogenic fate of the cell
Symmetric mitosis and cell fate correct answers increases the number of epithelial progenitor
cells
Asymmetric mitosis and cell fate correct answers results in daughter cells that delaminate from
epithelium and become neurons
Numb is first expressed apically in neural progenitors. In asymmetric divisions, Numb is
maintained only in _________ cells but not the __________. correct answers epithelial daughter
cells; delaminating neural precursor
(loss of Notch results in neuron path)
, Neurons arise first, then ______ correct answers glia
Radial glia cells divide to become correct answers oligodendrocytes, ependymal cells, astrocytes,
and neural stem cells
Site of primary neurogenesis in CNS correct answers Ventricular Zone
The rostral end of the neural tube differentiates to form 3 main cerebral vesicles: correct answers
Forebrain, midbrain, hindbrain
age-related location of neurons in cortical plate correct answers old neurons - bottom
new neurons - top
When postmitotic ventricular cells from young embryo (destined for deep cells) are transplanted
into the ventricular zone in older embryo (generating superficial cells), what is the fate of the
transplanted cell?
a. the transplanted postmitotic cells will adapt to the new host and develop as superficial cells
b. the transplanted postmitotic cells will not adapt to the new host and develop as deep cells
c. the transplanted postmitotic cells will continue growth as ventricular cells. correct answers b
When premitotic ventricular cells from the old embryo (generating superficial cells) are
transplanted into the ventricular zone in the younger embryo (destined for deep cells), what is the
fate of the transplanted cell? correct answers premitotic ventricular cells from old embryo takes
later fate (as if they were still in old embryo) in young host, and develop as superficial layers but
not old deep layers
These two cell types migrate vertically from ventricular zone by moving along radial glial fibers
correct answers pyramidal cells and astrocytes
Other multiple origins of layer I neurons include: correct answers rostral & basal forebrain,
cortical hem
Cell migration:
1. First neurons to migrate take up residence in the ________ layer which eventually disappears
2. Next cells to divide migrate to __________
3. The first to arrive become layer (VI/IV/V), followed by (V/VI/IV). This is called the _______
model, correct answers 1. "subplate/superficial"
2. cortical plate
3. VI; V; "inside out"
Rakic and Sidman (1973) radial glial cells correct answers - used golgi impregnation to map
radial glial cells in developing primate neocortex
- EM to visualize relationship of young neurons to glial fibers
Brain development begins as a correct answers tube (neural tube)
neural plate correct answers thickened region of the ectodermal layer that gives rise to the neural
tube. It is where progenitors for nervous system arise
2 molecular mechanisms of neural induction correct answers 1. BMP in ventral ectoderm
prevents neural induction and promotes epidermis formation
2. BMP inhibitors (Noggin, Chordin, Follistatin) induce neural tissue/plate in dorsal ectoderm
Once neurons are born, they migrate towards ______ of neural tube correct answers outskirts
_______ genes control regional identity and are expressed in different regions of AP axis and
DV axis correct answers homeobox (hox)
How do some cells in neuroectoderm become neuroblasts? correct answers 1. Proneural clusters
2. Lateral inhibition
Proneural clusters correct answers Clusters of cells that initiate neural fate
Lateral Inhibition correct answers Cells within proneural cluster interact to decide which cells
will become neuron
proneural genes correct answers - cause cells within proneural clusters to initiate a neural rather
than epidermal cell fate
- basic helix-loop-helix TFs
- equally expressed in cells w/in clusters
neurogenic genes encode __________ genes important for communication mechanisms that
mediate ___________ correct answers Notch signaling pathway (Notch, Delta, Suppressor of
Hairless); lateral inhibition
Notch signaling pathway activates bHLH TFs, like E(spl)-C, that functions in: correct answers
inhibiting proneural genes and neurogenic fate of the cell
Symmetric mitosis and cell fate correct answers increases the number of epithelial progenitor
cells
Asymmetric mitosis and cell fate correct answers results in daughter cells that delaminate from
epithelium and become neurons
Numb is first expressed apically in neural progenitors. In asymmetric divisions, Numb is
maintained only in _________ cells but not the __________. correct answers epithelial daughter
cells; delaminating neural precursor
(loss of Notch results in neuron path)
, Neurons arise first, then ______ correct answers glia
Radial glia cells divide to become correct answers oligodendrocytes, ependymal cells, astrocytes,
and neural stem cells
Site of primary neurogenesis in CNS correct answers Ventricular Zone
The rostral end of the neural tube differentiates to form 3 main cerebral vesicles: correct answers
Forebrain, midbrain, hindbrain
age-related location of neurons in cortical plate correct answers old neurons - bottom
new neurons - top
When postmitotic ventricular cells from young embryo (destined for deep cells) are transplanted
into the ventricular zone in older embryo (generating superficial cells), what is the fate of the
transplanted cell?
a. the transplanted postmitotic cells will adapt to the new host and develop as superficial cells
b. the transplanted postmitotic cells will not adapt to the new host and develop as deep cells
c. the transplanted postmitotic cells will continue growth as ventricular cells. correct answers b
When premitotic ventricular cells from the old embryo (generating superficial cells) are
transplanted into the ventricular zone in the younger embryo (destined for deep cells), what is the
fate of the transplanted cell? correct answers premitotic ventricular cells from old embryo takes
later fate (as if they were still in old embryo) in young host, and develop as superficial layers but
not old deep layers
These two cell types migrate vertically from ventricular zone by moving along radial glial fibers
correct answers pyramidal cells and astrocytes
Other multiple origins of layer I neurons include: correct answers rostral & basal forebrain,
cortical hem
Cell migration:
1. First neurons to migrate take up residence in the ________ layer which eventually disappears
2. Next cells to divide migrate to __________
3. The first to arrive become layer (VI/IV/V), followed by (V/VI/IV). This is called the _______
model, correct answers 1. "subplate/superficial"
2. cortical plate
3. VI; V; "inside out"
Rakic and Sidman (1973) radial glial cells correct answers - used golgi impregnation to map
radial glial cells in developing primate neocortex
- EM to visualize relationship of young neurons to glial fibers
