Module 2.1 Quiz
What determines whether a neuron has an action potential?
the combined effects of EPSPs and IPSPs
Spatial summation refers to ____.
multiple weak stimulations that occur at the same time
What do temporal summation and spatial summation have in common?
Both enable a reflex to occur in response to weak stimuli.
The primary difference between an EPSP and an action potential is that ____.
EPSPs are subthreshold events that decay over time and space
Which statement is TRUE about the spontaneous firing rates of neurons?
EPSPs increase the frequency.
Which statement is TRUE of EPSPs?
They decay over time and space.
On the basis of what evidence were the properties of synapses first inferred?
behavioral observations
Which process will most likely result in an IPSP?
chloride ions entering the cell
An EPSP is to ____ as an IPSP is to ____.
depolarization; hyperpolarization
When a vertebrate animal contracts the flexor muscles of a leg, it relaxes the extensor muscles of the same leg. Sherrington considered this evidence for the existence of ____.
inhibitory messages
In a reflex arc, the coordination between contraction of certain muscles and relaxation of others is mediated by ____.
interneurons
The "spontaneous firing rate" of a neuron refers to ____.
its rate of producing action potentials even when it is not stimulated
Which pattern of post-synaptic excitation will most likely result in an action potential?
rapid sequence of EPSPs
Temporal summation most likely occurs with ____.
rapid succession of subthreshold excitation
To measure temporal summation in single cells, researchers ____.
record depolarizations of the postsynaptic neuron
Even at rest, most neurons have periodic production of action potentials, known as the ____.
spontaneous firing rate
A certain weak stimulus produces no reflexive response, but a rapid repetition of that stimulus may produce such a response. What is this phenomenon called?
temporal summation
What causes an EPSP?
the opening of sodium channels
Sherrington deduced that transmission at a synapse must be slower than conduction along an axon. This was based on what kind of evidence?
the speed of reflexive responses
Temporal summation is to ____ as spatial summation is to ____.
time; location
