C. Week 3:Chemical Events at the Synapse
An EPSP is to ___ as an IPSP is to ___
Depolarization; hyperpolarization
A temporary hyperpolarization is known as an
IPSP
Temporal summation most likely occurs with
Rapid succession of sub threshold excitation
What causes an EPSP?
The opening of sodium channels
Which statement is TRUE about the spontaneous firing rates of neurons? Select one: a.EPSPs increase the frequency. b.EPSPs decrease the frequency. c.IPSPs increase the frequency. d.One EPSP equals the effect of two IPSPs.
a.EPSPs increase the frequency.
Exocytosis is the process by which neurotransmitters are ____. Select one: a.released from the presynaptic neuron b.synthesized c.destroyed d.secreted into synaptic vesicles
a.released from the presynaptic neuron
"Second messengers" carry their messages to ____. Select one: a.the presynaptic membrane b.areas within the postsynaptic cell c.areas within the presynaptic cell d.the surrounding glia
b.areas within the postsynaptic cell
"Transporter" proteins transport neurotransmitters ____. Select one: a.back into the presynaptic neuron b.across the synapse to the postsynaptic neuron c.across the synapse back to the presynaptic neuron d.to the appropriate receptor sites
c.across the synapse back to the presynaptic neuron
Autoreceptors monitor the ____. Select one: a.number of action potentials b.extracellular sodium concentration c.amount of neurotransmitter released d.amount of reuptake
c.amount of neurotransmitter released
Which process will most likely result in an IPSP?
c.chloride ions entering the cell
Which process will most likely result in an IPSP? Select one: a.potassium ions entering the cell b.sodium ions entering the cell c.chloride ions entering the cell d.chloride ions leaving the cell
c.chloride ions entering the cell
Vesicles are located ____. Select one: a.in postsynaptic terminals b.in dendrites c.in presynaptic terminals d.outside of the neuron in the extracellular fluid
c.in presynaptic terminals
The main advantage of a neuron releasing more than one neurotransmitter is that: Select one: a.if it runs out of one, it has others b.it can release different transmitters on different occasions c.it can send more complex messages d.it can release one from the axon's terminal and one from another location along the axon
c.it can send more complex messages
The amino acid tryptophan is the precursor to which neurotransmitter? Select one: a.dopamine b.endorphin c.serotonin d.nitric oxide
c.serotonin
Spatial summation refers to ____. Select one: a.multiple weak stimulations that occur in rapid succession b.a decrease in responsiveness after repeated stimulation c.multiple weak stimulations that occur at the same time d.an increase in the strength of action potentials after repeated stimulation
multiple weak stimulations that occur at the same time
Temporal summation is to ___ as spatial summation is to ___
time:space