Zaidi - Neural Development Flashcards
What happens during each of the three phases of neural development?
Phase 1: genesis of neurons and target cells.
Phase 2: outgrowth of axons and dendrites, and synapse formation. Both dendrites and axons have growth cones and the faster growth cone becomes the axon.
Phase 3: Synaptic refinement.
The CNS is derived from the ___. The PNS is derived from the ___.
neural tube.
neural crest.
___ cells originate at the dorsal end of the neural tube. They migrate extensively during or shortly after closure of the neural tube, or ___. They generate several differentiated cell types, including ___-producing cells of the adrenal gland.
Fate of the neural crest cells depends on what?
Neural crest.
Neurulation.
epinephrine.
Fate of the cells depends on where they migrate to and settle.
The dorsal roof plate secretes these two protein morphogens, __ and __.
The ventral floor plate and notochord secretes this morphogen ___.
BMP and Wnt.
Sonic hedgehog.
The monomeric GTPases __ and __ control the assembly/disassembly of __ filaments, which control movement of the growth cone.
Growth cones also throw out __ and __ to migrate.
Rho and Rac.
actin.
filopodia and lamelopodia.
Growth cones find their way by exploiting two major cues. What are they?
cone receptors sense the extracellular matrix environment and chemotactic factors released by neighboring cells.
These two classes of homophilic cell adhesion molecules, ___ and ___, provide a mechanism for selective guidance and recognition
immunoglobulin superfamily and cadherin family.
This matrix molecule, ___ favors axonal outgrowth.
This matrix molecule, ___ inhibits growth.
laminin.
chondroitin sulfate. proteoglycans.
Dorsal neurons are ___.
Ventral clusters of spinal cord neurons are ___.
The intermediate location has these types of neurons: ___.
sensory.
motor.
inter-neurons.
What are 6 mechanisms of growth cone guidance?
- extracellular matrix adhesion.
- cell surface adhesion.
- guidance by pioneer neuron.
- chemoattraction.
- contact inhibition.
- chemorepulsion.
During commissural neuron guidance, floor plate cells secrete ___, and binding causes opening of ___ channels. This causes entry of extracellular ___, leading to activation/movement of growth cone.
netrin.
TRPC (Transient receptor potential C).
calcium.
Midline cells secrete ___, which repels growth cones and blocks entry to the midline, and its receptor, ___, is found on commissural neurons.
Another growth cone repellant is ___.
slit.
roundabout.
semaphorin.
The target cells produce limited amount of specific ___ factors needed for survival of the neuron.
neurotrophic.
Synaptic remodeling of retinal/tectal neurons depend on ___ and ___.
___ retinal neuron axons prefer anterior tectal neurons, ___ retinal neurons have no preference.
spatial order and activity-dependent.
Posterior.
Anterior.
Neurons that fire together wire together. Entry of calcium through the ___ receptor (a type of glutamate receptor) triggers lasting change in synaptic strength. This can cause remodeling of dendritic ___.
NMDA.
spines.
