PSIO 305 Exam 1 Question and
answers correctly solved 2025/2026
An increase in ALL of the following would suggest trophic communication or support EXCEPT:
1.# of dendrites & synaptic terminals
2.Size of primary sensory cortex area receiving input from finger
3.Rate of respiration with exercise
4.Density of glial cells in memory areas - correct answer ✔3.Rate of respiration with exercise
a "Do " communication: a relatively short term 'call to action' (activation) of the respiratory muscles to
meet the immediate demands of exercise: increased need of oxygen and removal of CO2.T he remainder
are longer term responses to trophic input, promoting structural and/or functional changes in the cells
or tissues involved
What is systemic communication? - correct answer ✔Response to momentary stimulus or demand; can
be Acute or short-term in order to maintain homeostasis
-May be an integrated system response
What is trophic communication? - correct answer ✔Promotes cell growth, differentiation, survival
-Long term (or longer) effects
-Robust phenomenon
-sensitive to changes in age, activity, pathology, and nutrition
What do Trophic Interactions between Cells & Tissues promote? - correct answer ✔Growth,
Differentiation, & Survival
What are the differences between fast and slow synapses? - correct answer ✔Fast- Activate ion
channels (ionotropic), Current flow/voltage change
,Slow- Binds to G-protein coupled receptors (GPCR)(metabotropic), Downstream, slower and more long
lasting effect
What is the effect of dopamine on fast and slow synapses? - correct answer ✔Fast- Activate ion
channels, In Basal Ganglia, Affects movement planning "Do" communication, but can be 'trophic' as well
Slow- Binds to GPCR, In Hypothalamus, Involved in hunger, thirst, temp regulation, Trophic
What are the trophic importances of glia cells (neuroglia)? - correct answer ✔•Regulation of
environment- Ion channels, Transporters
•Regulation of growth via release of glia-derived growth factor
(also supportive and help insulate)
how do you 'know' how strong the stimulus is? - correct answer ✔Rate coding: AP frequency is
proportional to stimulus intensity
-Greater open time or distortion of channel: > greater ion flux and voltage changes, > potential for
reaching threshold, increased # of action potentials
How to indicate character of stimulus? (i.e, how do you 'know' the speed of onset or rate of
adaptation?) - correct answer ✔Pattern Coding: Pattern Indicates type of stimulus and responsiveness
of sensory receptor
What is temporal summation? - correct answer ✔•a single source
•With multiple signals
•Over a short time
•Voltage change builds
What is spatial summation? - correct answer ✔•Simultaneous arrival of multiple inputs, Spatially
separated
-if one at a time: small voltage change for each channel alone
, -If simultaneous: Voltage change reflects the sum of the ion flux through all theopen channels.
What is the result of both temporal and spatial summation? - correct answer ✔Both types of
summation: increase release of NT's, open channel time, ion flux and voltage change
What is a motor unit and what does it consist of? - correct answer ✔•Smallest functional unit for
voluntary force production
•Consists of: Motoneuron, the subset of muscle fibers it innervates
With aging, there is a loss of motor neurons and a subsequent loss of motor units (MU). The remaining
motor neurons often 'pick up' new fibers, providing innervation to some of the abandoned muscle
fibers. This new MU arrangement might lead to which of the following in the elderly?
1.Increased overall strength
2.Increased proprioception
3.Decreased precision of movement
4.Decreased ability for temporal summation - correct answer ✔3.Decreased precision of movement
Remaining MU's are larger, reducing ability to finely increase or decrease forces for movement control
and adjustments
What are muscle Fiber types categorized based on? - correct answer ✔•Contractile speed
•Fiber diameter
•Metabolic preferences
•Fatiguability
What is a sarcomere made up of? - correct answer ✔•Contractile repeating unit
•Bounded by Z disc/line
•Thin filaments-Actin
answers correctly solved 2025/2026
An increase in ALL of the following would suggest trophic communication or support EXCEPT:
1.# of dendrites & synaptic terminals
2.Size of primary sensory cortex area receiving input from finger
3.Rate of respiration with exercise
4.Density of glial cells in memory areas - correct answer ✔3.Rate of respiration with exercise
a "Do " communication: a relatively short term 'call to action' (activation) of the respiratory muscles to
meet the immediate demands of exercise: increased need of oxygen and removal of CO2.T he remainder
are longer term responses to trophic input, promoting structural and/or functional changes in the cells
or tissues involved
What is systemic communication? - correct answer ✔Response to momentary stimulus or demand; can
be Acute or short-term in order to maintain homeostasis
-May be an integrated system response
What is trophic communication? - correct answer ✔Promotes cell growth, differentiation, survival
-Long term (or longer) effects
-Robust phenomenon
-sensitive to changes in age, activity, pathology, and nutrition
What do Trophic Interactions between Cells & Tissues promote? - correct answer ✔Growth,
Differentiation, & Survival
What are the differences between fast and slow synapses? - correct answer ✔Fast- Activate ion
channels (ionotropic), Current flow/voltage change
,Slow- Binds to G-protein coupled receptors (GPCR)(metabotropic), Downstream, slower and more long
lasting effect
What is the effect of dopamine on fast and slow synapses? - correct answer ✔Fast- Activate ion
channels, In Basal Ganglia, Affects movement planning "Do" communication, but can be 'trophic' as well
Slow- Binds to GPCR, In Hypothalamus, Involved in hunger, thirst, temp regulation, Trophic
What are the trophic importances of glia cells (neuroglia)? - correct answer ✔•Regulation of
environment- Ion channels, Transporters
•Regulation of growth via release of glia-derived growth factor
(also supportive and help insulate)
how do you 'know' how strong the stimulus is? - correct answer ✔Rate coding: AP frequency is
proportional to stimulus intensity
-Greater open time or distortion of channel: > greater ion flux and voltage changes, > potential for
reaching threshold, increased # of action potentials
How to indicate character of stimulus? (i.e, how do you 'know' the speed of onset or rate of
adaptation?) - correct answer ✔Pattern Coding: Pattern Indicates type of stimulus and responsiveness
of sensory receptor
What is temporal summation? - correct answer ✔•a single source
•With multiple signals
•Over a short time
•Voltage change builds
What is spatial summation? - correct answer ✔•Simultaneous arrival of multiple inputs, Spatially
separated
-if one at a time: small voltage change for each channel alone
, -If simultaneous: Voltage change reflects the sum of the ion flux through all theopen channels.
What is the result of both temporal and spatial summation? - correct answer ✔Both types of
summation: increase release of NT's, open channel time, ion flux and voltage change
What is a motor unit and what does it consist of? - correct answer ✔•Smallest functional unit for
voluntary force production
•Consists of: Motoneuron, the subset of muscle fibers it innervates
With aging, there is a loss of motor neurons and a subsequent loss of motor units (MU). The remaining
motor neurons often 'pick up' new fibers, providing innervation to some of the abandoned muscle
fibers. This new MU arrangement might lead to which of the following in the elderly?
1.Increased overall strength
2.Increased proprioception
3.Decreased precision of movement
4.Decreased ability for temporal summation - correct answer ✔3.Decreased precision of movement
Remaining MU's are larger, reducing ability to finely increase or decrease forces for movement control
and adjustments
What are muscle Fiber types categorized based on? - correct answer ✔•Contractile speed
•Fiber diameter
•Metabolic preferences
•Fatiguability
What is a sarcomere made up of? - correct answer ✔•Contractile repeating unit
•Bounded by Z disc/line
•Thin filaments-Actin
