Synaptic Plasticity

Question 1

Key variables that characterize quantal release

Answer 1

• the number of release sites (N)
• the probability of a quantal release (p)
• the size of the quantal response (q)

Question 2

the number of release sites (N)

morphological correlate

Answer 2

number of active zones/synapses

Question 3

the probability of a quantal release (p)

morphological correlate

Answer 3

number of docked vesicles

Question 4

the size of the quantal response (q)

morphological correlate

Answer 4

single vesicle and/or the response to a single vesicle (receptor sensitivity)

Question 5

Forms of plasticity are distinguished by

Answer 5

Duration
Site of expression
Direction of effect
Source of induction

Question 6

Forms of plasticity distinguished by:

Duration

Answer 6

Short term – msec to minutes

Long term – hours to days, weeks, or longer

Question 7

Forms of plasticity distinguished by:

Direction of effect

Answer 7

enhancement

depression

Question 8

Forms of plasticity distinguished by:

Source of induction

Answer 8

homosynaptic – intrinsic to synapse

heterosynaptic – third neuron involved

Question 9

Forms of plasticity distinguished by:

Site of expression

Answer 9

both homo- and heterosynaptic expression
presynaptic: change in amount of transmitter released
postsynaptic: change in response to transmitter released leads to changes in sensitivity and number of receptors.
Intracellular mechanisms that regulate membrane excitability
Synaptic cleft