NEUROSCIENCE EVALUATION UPDATED EXAMS
QUESTIONS AND ANSWERS SURE A+
✔✔Postsynaptic Components - ✔✔much simpler than presynaptic neurons
most significant feature of postsynaptic neurons is the postsynaptic density (PSD)
∙analogous to the presynaptic dense grid
∙involved in organizing the postsynaptic receptors and positioning second messenger
and cellular signaling pathways
∙couples synaptic activity with postsynaptic responses through acute events that only
occur with thre presence of NTs bound to receptors
also contain polyribosomes, smooth ER and endosomes that have similar functions to
presynaptic neuron components
∙major difference is lack of local mitochondria
✔✔Types of Synapses - ✔✔named for where they occur along the postsynaptic neuron
axosomatic dendrites occur when the presynaptic axon interacts with the postsynaptic
cell body
∙inhibitory
∙GABAergic or glycinergic
,axo-axonic synapses occur when the presynaptic axon interacts with a point along the
postsynaptic axon
∙tend to have a neuromodulatory role and are involved in presynaptic inhibition
Axodendritic synapses occur when the presynaptic axon interacts with a postsynaptic
dendrite
∙excitatory
∙can be directly on the dendrite, a shaft synapse or can be on a dendritic spine
✔✔Dendritic Spines - ✔✔small protrusions from dendrites that form a concentrated
reservoir of signaling and biochemical mechanisms
reservoir is formed due to bottlenecking that limits the rate of diffusion to the rest of the
cell
come in a variety of shapes and sizes, each of which serves a unique function
classified based on their shape: stubby, thin, mushroom or cup
development of dendritic spine synapses is directed by filopodium that locate and
recognize appropriate presynaptic axons and guide them to the dendrites
size of the spine has a direct correlation to its function
∙small spines are involved in plasticity and development and are implicated in
neurological impairment associated with traumatic brain injuries
∙large spines are associated with learning and memory due to their larger contact areas
that can interact with more NTs and generate larger functions
∙abnormal spine numbers or shapes are associated with a variety of nervous system
disorders, including Alzheimer's, in which small spines are lost early before there are
any other noticeable impairments
✔✔Morphological Classification of Synapses - ✔✔Gray type I synapses are excitatory
(glutamatergic) and typically are axodendritic
∙type I synapses have round synaptic vesicles, large active zone and synaptic cleft, and
a single continuous postsynaptic density
Gray type II synapses are inhibitory (GABAergic), typically axosomatic
∙have flattened synaptic vesicles, small active zone and synaptic cleft, and multiple
"perforated" postsynaptic densities
✔✔Vesicle Release - ✔✔synaptic vesicle/NT release happens when the AP depolarizes
the membrane, which opens the voltage-gated Ca2+ channels allowing fusion of
synaptic vesicles with the membrane and release of NTs
vesicle is then recovered from the membrane, and may re-uptake NTs, and is
processed and recycled
, ✔✔Postsynaptic responses: Excitatory Postsynaptic Potentials (EPSP) vs. Inhibitory
Postsynaptic Potentials (IPSP) - ✔✔EPSP increase the likelihood of triggering an AP in
the postsynaptic neuron
IPSP decrease the likelihood of triggering an AP
✔✔Classification of Memory - ✔✔basal ganglia play a role in implicit memory, which
relates to procedural memory of skills and tasks
hippocampus is primary site of explicit memory (memory of facts and experiences)
✔✔How does information storage and memory formation occur? - ✔✔glutamate
receptors (particularly NMDA receptors) are the main players
✔✔Fragile X Syndrome - ✔✔most common single gene inherited form of mental
retardation
X chromosome is basically messed up
this, along will Down syndrome, will have weird looking dendritic processes
✔✔Alzheimer's Disease - ✔✔extreme shrinkage of the hippocampus (which is why they
have memory deficits) and the cerebral cortex
huge enlargement of the ventricles
✔✔Hebb's Postulate - ✔✔when an axon of Cell A plays a role in repeatedly firing a
nearby Cell B, a growth process or metabolic change will occur in Cell A, Cell B, or
BOTH cells where Cell A's efficiency in firing Cell B increases
✔✔Neurons that fire together, wire together: An introduction to LTP - ✔✔diagram shows
that one postsynaptic neuron receives competing input from both let and right eyes
∙look at the left eye → higher frequency right means that those synapses will be
strengthened and now the postsynaptic neuron will preferentially receive input from the
left eye
∙b/c right eye wasn't firing as often, synapses weakened and eventually were eliminated
✔✔Synaptogenesis - ✔✔synapses can be formed along the actual length of the axon
even upstream of the boutons
∙called "En Passant" synapses
potential synapses will always be exposed to a bunch of different molecules/gene
roducts that can either strengthen or eliminate the synapses
QUESTIONS AND ANSWERS SURE A+
✔✔Postsynaptic Components - ✔✔much simpler than presynaptic neurons
most significant feature of postsynaptic neurons is the postsynaptic density (PSD)
∙analogous to the presynaptic dense grid
∙involved in organizing the postsynaptic receptors and positioning second messenger
and cellular signaling pathways
∙couples synaptic activity with postsynaptic responses through acute events that only
occur with thre presence of NTs bound to receptors
also contain polyribosomes, smooth ER and endosomes that have similar functions to
presynaptic neuron components
∙major difference is lack of local mitochondria
✔✔Types of Synapses - ✔✔named for where they occur along the postsynaptic neuron
axosomatic dendrites occur when the presynaptic axon interacts with the postsynaptic
cell body
∙inhibitory
∙GABAergic or glycinergic
,axo-axonic synapses occur when the presynaptic axon interacts with a point along the
postsynaptic axon
∙tend to have a neuromodulatory role and are involved in presynaptic inhibition
Axodendritic synapses occur when the presynaptic axon interacts with a postsynaptic
dendrite
∙excitatory
∙can be directly on the dendrite, a shaft synapse or can be on a dendritic spine
✔✔Dendritic Spines - ✔✔small protrusions from dendrites that form a concentrated
reservoir of signaling and biochemical mechanisms
reservoir is formed due to bottlenecking that limits the rate of diffusion to the rest of the
cell
come in a variety of shapes and sizes, each of which serves a unique function
classified based on their shape: stubby, thin, mushroom or cup
development of dendritic spine synapses is directed by filopodium that locate and
recognize appropriate presynaptic axons and guide them to the dendrites
size of the spine has a direct correlation to its function
∙small spines are involved in plasticity and development and are implicated in
neurological impairment associated with traumatic brain injuries
∙large spines are associated with learning and memory due to their larger contact areas
that can interact with more NTs and generate larger functions
∙abnormal spine numbers or shapes are associated with a variety of nervous system
disorders, including Alzheimer's, in which small spines are lost early before there are
any other noticeable impairments
✔✔Morphological Classification of Synapses - ✔✔Gray type I synapses are excitatory
(glutamatergic) and typically are axodendritic
∙type I synapses have round synaptic vesicles, large active zone and synaptic cleft, and
a single continuous postsynaptic density
Gray type II synapses are inhibitory (GABAergic), typically axosomatic
∙have flattened synaptic vesicles, small active zone and synaptic cleft, and multiple
"perforated" postsynaptic densities
✔✔Vesicle Release - ✔✔synaptic vesicle/NT release happens when the AP depolarizes
the membrane, which opens the voltage-gated Ca2+ channels allowing fusion of
synaptic vesicles with the membrane and release of NTs
vesicle is then recovered from the membrane, and may re-uptake NTs, and is
processed and recycled
, ✔✔Postsynaptic responses: Excitatory Postsynaptic Potentials (EPSP) vs. Inhibitory
Postsynaptic Potentials (IPSP) - ✔✔EPSP increase the likelihood of triggering an AP in
the postsynaptic neuron
IPSP decrease the likelihood of triggering an AP
✔✔Classification of Memory - ✔✔basal ganglia play a role in implicit memory, which
relates to procedural memory of skills and tasks
hippocampus is primary site of explicit memory (memory of facts and experiences)
✔✔How does information storage and memory formation occur? - ✔✔glutamate
receptors (particularly NMDA receptors) are the main players
✔✔Fragile X Syndrome - ✔✔most common single gene inherited form of mental
retardation
X chromosome is basically messed up
this, along will Down syndrome, will have weird looking dendritic processes
✔✔Alzheimer's Disease - ✔✔extreme shrinkage of the hippocampus (which is why they
have memory deficits) and the cerebral cortex
huge enlargement of the ventricles
✔✔Hebb's Postulate - ✔✔when an axon of Cell A plays a role in repeatedly firing a
nearby Cell B, a growth process or metabolic change will occur in Cell A, Cell B, or
BOTH cells where Cell A's efficiency in firing Cell B increases
✔✔Neurons that fire together, wire together: An introduction to LTP - ✔✔diagram shows
that one postsynaptic neuron receives competing input from both let and right eyes
∙look at the left eye → higher frequency right means that those synapses will be
strengthened and now the postsynaptic neuron will preferentially receive input from the
left eye
∙b/c right eye wasn't firing as often, synapses weakened and eventually were eliminated
✔✔Synaptogenesis - ✔✔synapses can be formed along the actual length of the axon
even upstream of the boutons
∙called "En Passant" synapses
potential synapses will always be exposed to a bunch of different molecules/gene
roducts that can either strengthen or eliminate the synapses
