OCCTH 585 MIDTERM 1 QUESTIONS
AND ANSWERS 100% CORRECT
evidence for a plastic brain - ANSWER-- learning and memory
- skill acquisition
- development
- aging
- injury and disease
- recovery
neuron - ANSWER-cell that allows transmission of information
dendrites - ANSWER-collects/receives information from other sources
cell body - ANSWER-integrates incoming signals and generates outgoing signal to the
axon; powerhouse of the cell
axon - ANSWER-passes electrical signals (action potential) to dendrites of another cell
or to an effector cell
synaptic bouton - ANSWER-a specialized area within the axon of the presynaptic cell
that contains neurotransmitters enclosed in small membrane-bound spheres called
synaptic vesicles
information flow through neurons - ANSWER-dendrites receive information, cell body
integrates and generates outgoing signal, information is summated at the axon hillock,
axon carries action potential to synaptic bouton, synaptic bouton releases
neurotransmitters into the synaptic cleft where they diffuse across and interact with the
post-synaptic cell (neuron or effector cell)
EPSP - ANSWER-excitatory post synaptic potential- closer to an action potential,
depolarizing
IPSP - ANSWER-inhibitory post synaptic potential - further from an action potential,
polarizing
action potential - ANSWER-the all-or-none electrical signal that travels down a neuron's
axon - result of the spatial/temporal summation of EPSPs and IPSPs
neuroplasticity - ANSWER-- change in the properties of neurotransmission
- change in cell properties
- structural/anatomical changes of cells
,change in properties of neurotransmission - ANSWER-- change in NT release
- change in post-synaptic potential size/shape
change in cell properties - ANSWER-- size and shape
- electrical properties (resistance)
- leakiness
axonal growth during embryology - ANSWER-- chemoattractants and chemorepellants
work together to repel axon from wrong target and attract to correct target
- neurons are in growth phase; grow with a growth cone
- guide cells are present
- hormone balance is critical
- guidance molecules present in high concentrations
chemoattractant - ANSWER-a diffusible molecule that acts over a distance to attract
growing axons
chemorepellant - ANSWER-a diffusible molecule that acts over a distance to repel
growing axons
growth cone - ANSWER-the specialized structure specific for growth - filipodium
(extensions) go out in all directions searching for chemoattractants, which will cause it
to grow in a dedicated direction to the target
impact of hormones on baby during embryology - ANSWER-important for timing of
growth events, and the responsiveness of the neuron
structural/anatomical changes of cells - ANSWER-- re-growth of parts of the nervous
system (not there yet)
- growth of axons, dendrites, axonal collateral
unmasking - ANSWER-immediate, exposure of pre-existing synapses resulting in
functional changes - synapses were always there, but may not of been functionally
recognized
dendritic pruning - ANSWER-retraction of unused bits (ex. dendritic spines/branches),
resulting in a loss in real estate and a decrease in energy expenditure - after un-
masking occurs, dendrites will wait for input, but it they don't receive any this process
will take place resulting in a reduction in cell volume impacting cell function
collateral sprouting - ANSWER-growth of new bits (axon branches), requiring time, to fill
vacancies on dendrites/target - process is activity dependent and produces functional
changes
, how is growth is activity dependent? - ANSWER-target cells send out signals for other
cells to grow towards them - the only way for a cell to grow towards the target cell is if it
is also active:
- active cells release NT and then "scoop" in excess NT - with this, they will bring in
chemicals from the target cell (neurotrophins/chemoattractants), attracting cell to grow
towards target
- dendritic spines release neurotrophins to stabalize the synapse - if the input cell dies,
the neurotrophins release into environment, attacting cells to fill in vacant space
can we stimulate collateral sprouting? - ANSWER-yes, via high frequency and intensity
stimulation - tells the nervous system the input is important, because we are receiving a
lot of stimulation - so this drives anatomical and functional changes that support efficacy
of the stimulated system
neurogenesis - ANSWER-formation of new neurons
neurogenesis in the mature CNS - ANSWER-- dentate gyrus of the hippocampus
- corpus collosum - olfactory bulb
- neural glial cells - astrocytes
mechanism/control of neurogenesis - ANSWER-VERY COMPLEX
- Proliferation (if not well controlled = tumours)
- Migration (need to move to intended target, survive hostile environment from immune
system)
- Differentiation (need to differentiate from stem cell to functional neuron capable of
making connections)
**new neurons survive in enriched environments, glucocorticoids (stress) decrease
proliferation, estrogen increases cell proliferation
limitations of neurogenesis in mature CNS - ANSWER-- happens in embryology
- need to navigate around pre-existing and formed structures
- hormones and environment impact and influence how cells shift from one stage to the
next
- complicated by embedding a new cell into a system that we have created over a
lifetime
guidance molecules - ANSWER-- netrin
- slit
- ephrin
- semaphorin
netrin - ANSWER-growth promoter/chemoattractant
slit - ANSWER-both a chemoattractant and a chemorepellant - depends on the cell that
is receiving the signal - can also switch depending on stage of development (bringing an
axon to it, then repelling it)
AND ANSWERS 100% CORRECT
evidence for a plastic brain - ANSWER-- learning and memory
- skill acquisition
- development
- aging
- injury and disease
- recovery
neuron - ANSWER-cell that allows transmission of information
dendrites - ANSWER-collects/receives information from other sources
cell body - ANSWER-integrates incoming signals and generates outgoing signal to the
axon; powerhouse of the cell
axon - ANSWER-passes electrical signals (action potential) to dendrites of another cell
or to an effector cell
synaptic bouton - ANSWER-a specialized area within the axon of the presynaptic cell
that contains neurotransmitters enclosed in small membrane-bound spheres called
synaptic vesicles
information flow through neurons - ANSWER-dendrites receive information, cell body
integrates and generates outgoing signal, information is summated at the axon hillock,
axon carries action potential to synaptic bouton, synaptic bouton releases
neurotransmitters into the synaptic cleft where they diffuse across and interact with the
post-synaptic cell (neuron or effector cell)
EPSP - ANSWER-excitatory post synaptic potential- closer to an action potential,
depolarizing
IPSP - ANSWER-inhibitory post synaptic potential - further from an action potential,
polarizing
action potential - ANSWER-the all-or-none electrical signal that travels down a neuron's
axon - result of the spatial/temporal summation of EPSPs and IPSPs
neuroplasticity - ANSWER-- change in the properties of neurotransmission
- change in cell properties
- structural/anatomical changes of cells
,change in properties of neurotransmission - ANSWER-- change in NT release
- change in post-synaptic potential size/shape
change in cell properties - ANSWER-- size and shape
- electrical properties (resistance)
- leakiness
axonal growth during embryology - ANSWER-- chemoattractants and chemorepellants
work together to repel axon from wrong target and attract to correct target
- neurons are in growth phase; grow with a growth cone
- guide cells are present
- hormone balance is critical
- guidance molecules present in high concentrations
chemoattractant - ANSWER-a diffusible molecule that acts over a distance to attract
growing axons
chemorepellant - ANSWER-a diffusible molecule that acts over a distance to repel
growing axons
growth cone - ANSWER-the specialized structure specific for growth - filipodium
(extensions) go out in all directions searching for chemoattractants, which will cause it
to grow in a dedicated direction to the target
impact of hormones on baby during embryology - ANSWER-important for timing of
growth events, and the responsiveness of the neuron
structural/anatomical changes of cells - ANSWER-- re-growth of parts of the nervous
system (not there yet)
- growth of axons, dendrites, axonal collateral
unmasking - ANSWER-immediate, exposure of pre-existing synapses resulting in
functional changes - synapses were always there, but may not of been functionally
recognized
dendritic pruning - ANSWER-retraction of unused bits (ex. dendritic spines/branches),
resulting in a loss in real estate and a decrease in energy expenditure - after un-
masking occurs, dendrites will wait for input, but it they don't receive any this process
will take place resulting in a reduction in cell volume impacting cell function
collateral sprouting - ANSWER-growth of new bits (axon branches), requiring time, to fill
vacancies on dendrites/target - process is activity dependent and produces functional
changes
, how is growth is activity dependent? - ANSWER-target cells send out signals for other
cells to grow towards them - the only way for a cell to grow towards the target cell is if it
is also active:
- active cells release NT and then "scoop" in excess NT - with this, they will bring in
chemicals from the target cell (neurotrophins/chemoattractants), attracting cell to grow
towards target
- dendritic spines release neurotrophins to stabalize the synapse - if the input cell dies,
the neurotrophins release into environment, attacting cells to fill in vacant space
can we stimulate collateral sprouting? - ANSWER-yes, via high frequency and intensity
stimulation - tells the nervous system the input is important, because we are receiving a
lot of stimulation - so this drives anatomical and functional changes that support efficacy
of the stimulated system
neurogenesis - ANSWER-formation of new neurons
neurogenesis in the mature CNS - ANSWER-- dentate gyrus of the hippocampus
- corpus collosum - olfactory bulb
- neural glial cells - astrocytes
mechanism/control of neurogenesis - ANSWER-VERY COMPLEX
- Proliferation (if not well controlled = tumours)
- Migration (need to move to intended target, survive hostile environment from immune
system)
- Differentiation (need to differentiate from stem cell to functional neuron capable of
making connections)
**new neurons survive in enriched environments, glucocorticoids (stress) decrease
proliferation, estrogen increases cell proliferation
limitations of neurogenesis in mature CNS - ANSWER-- happens in embryology
- need to navigate around pre-existing and formed structures
- hormones and environment impact and influence how cells shift from one stage to the
next
- complicated by embedding a new cell into a system that we have created over a
lifetime
guidance molecules - ANSWER-- netrin
- slit
- ephrin
- semaphorin
netrin - ANSWER-growth promoter/chemoattractant
slit - ANSWER-both a chemoattractant and a chemorepellant - depends on the cell that
is receiving the signal - can also switch depending on stage of development (bringing an
axon to it, then repelling it)
