10b: Cortex II (Development) Flashcards
Which foramen connects lateral ventricles to the subsequent (X) ventricle?
X = third
Foramen of Monro
During development, the hemispheres first grow/expand in which direction(s) to form (X) lobe?
Forward
X = frontal lobe
During development, the hemispheres grow/expand upward/laterally to form (X) lobe/area?
X = parietal
During development, the hemispheres grow/expand posteriorly to form (X) lobe/area?
X = occipital
During development, the hemispheres grow/expand inferiorly to form (X) lobe/area?
X = temporal
The temporal lobe is marked during development by indentation called (X), which grows backwards. Inside the area of (X) is the future (Y).
X = lateral fissure; Y = insula
List the commissures that appear during development, in the order which they appear.
- Anterior
- Commissure of fornix
- Corpus callosum
The anterior commissure connects:
Olfactory bulb and portions of temporal lobes
The thin wall of hemispheres extending vertically from corpus callosum to (X) is called (Y).
X = fornix Y = septum pellucidum
T/F: Neuro-epithleium of cerebral hemispheres is much like the epithelium of rest of neural tube.
True
Neuroepithelium of cerebral hemispheres is (single/multi)-layered (X) type of epithelium.
Single;
X = pseudo stratified
Neuroepithelium of cerebral hemispheres has zones that differ based on:
Density of cells within zone
The marginal zone of cerebral hemisphere is near (X) and is cell-(sparse/dense).
X = the pia
Sparse
The ventricular zone of cerebral hemisphere is near (X) and is cell-(sparse/dense).
X = ventricles
Dense
The (marginal/ventricular) zone of neuro-epithelium consists of (X) cells, which eventually divide/differentiate to generate (Y) of cortex.
Ventricular;
X = neuroblasts;
Y = pyramidal neurons and glia
Cerebral cortex development: A dividing (X) translocates its nucleus through cytoplasm from (Y) to (Z).
X = neuroblast; Y = ventricular margin Z = marginal zone
Then back to ventricular margin
Cerebral cortex development: The (X) cell divides at which border/zone?
X = neuroblast;
At ventricular margin
Cerebral cortex development: If plane of (X) during cell division is vertical, aka (symmetrical/asymmetrical) division, what’s the fate of the daughter cells?
X = cleavage;
Symmetrical;
Both will become neuroblasts OR neurons
Neural precursors initially divide (symmetrically/asymmetrically). Gradually, the percent of (symmetrical/asymmetrical) divisions increases.
Asymmetrically; symmetrical
Cerebral cortex development: If plane of (X) during cell division is horizontal, aka (symmetrical/asymmetrical) division, what’s the fate of the daughter cells?
X = cleavage;
Asymmetrical;
One will be neuroblast, the other a neuron/glial cell
Newly generated neurons migrate on (X) to (Y) surface, where they accumulate in a layer of cells called (Z).
X = radial glial fibers; Y = pial Z = cortical plate
First neuroblasts to differentiate will do so to become (X) cells.
X = radial glia
The most recently generate neurons are located at (base/superficial surface) of cortical plate.
Superficial surface
During development, cortical plate will become widely separated from (X) zone via formation of (Y) zone. This is due to (growth/invasion) of axons.
X = ventricular Y = intermediate
Both! Growth of cortical plate axons and invasion of thalamic axons
The intermediate zone of the developing cortex will eventually become:
Subcortical white matter
During cortical development, migration of neurons differs based on which characteristic?
Whether they’re excitatory or inhibitory
Inhibitory neurons undergo (X) migration, traveling on (Y) cells.
X = tangential (neurophilic); Y = other neurons
Excitatory neurons undergo (X) migration, traveling on (Y) cells.
X = radial (gliophilic); Y = radial glial
T/F: Cell generation/differentiation of cortex continues postnatally.
True
T/F: The cortical plate persists in adults.
False - becomes neocortex (cells in layers 2-6)
Fate of ventricular zone of cortex in adult.
Becomes ependymal layer and sub-ventricular zone
When neuronal migration is complete, many radial glia transform into (X).
X = astrocytes
The migrating neurons are (unipolar/bipolar) in form. They send out branches to form (dendrites/local plexuses) first.
Bipolar;
Both simultaneously
During development of cortex, there’s extensive (over/under)-production of (X), which are then “pruned” (before/after) birth.
Over;
X = synapses;
After
T/F: There are many abnormal axonal projections during development.
True - subject to pruning
T/F: Association cortices are located immediately adjacent to their respectful primary areas.
True
All association areas adjacent to the primary areas are (unimodal/multimodal). The information is then transmitted to (unimodal/multimodal) (X) areas.
Unimodal;
Multimodal;
X = association
The Protomap theory proposes that:
Fate of neurons is determined very early, prior to migration into cortex
The Protocortex theory proposes that:
Cortical areas become specified as consequence of other factors (i.e. thalamic input)
The (X) theory suggests that a “map” of cortical areas is programmed within the neurons.
X = protomap
Ocular dominance columns receiving input from deprived eye become more narrow than those receiving input from functional eye. This supports (protomap/protocortex) theory.
Protocortex
Radical rewiring describes which phenomenon? It supports the (protomap/protocortex) theory.
Protocortex;
Cortex that would normally subserve one sensory function can assume a completely different role (in radical situation)
List the potential methods by which the number of cortical areas can expand.
- Existing areas subdivide
- New area appears and is maintained due to evolutionary advantage
- New association cortex/area added onto existing cortex
(Neuro/glio)-genesis peaks first, so most (X) cells generated late in development, from (Y) zone.
Neurogenesis;
X = glial
Y = subventricular
T/F: Glial cells continue to be produced throughout life.
True
T/F: Myelination is complete in the second year of life in humans.
False - not until early adulthood
T/F: Neurogenesis has stopped postnatally.
False - continues through year 2 in humans