AP 1 (11-7)
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AP 1 (11-7)
AP 1 chapter 11.
A _____ is conducted as an action potential is reached at the trigger zone.
Nerve impulses spread by a _____ flowing down the fiber, and adjacent areas of the membrane reach action potential.
Greater intensity of stimulation triggers more_____, not stronger impulses.
impulses per second
What is a Refractory period?
brief period during a nerve impulse when a stimulus will not trigger another action potential
The recractory period does what two things?
limits the frequency of impulses in a neuron
ensures that the impulse propagates in one direction down the axon
_____ fibers conduct impulses over their entire membrane surface.
What is saltatory conduction?
Myelinated fibers conducting impulses from one Node of Ranvier to the next.
Saltatory conduction is _____ than conduction on unmyelinated neurons.
The junction between two communicating neurons is called a _____.
In the synapse there exists a _____ between them across which the impulse must be conveyed.
What is a synapse?
The process by which the impulse in the presynaptic neuron is transmitted across the synaptic cleft to the postsynaptic neuron is called synaptic transmission.
When an impulse reaches the synaptic knobs of an axon, synaptic vesicles release a _____ into the _____.
Neurotransmitters that increase postsynaptic membrane permeability to sodium ions may trigger impulses and are thus _____.
Neurotransmitters may decrease membrane permeability to sodium ions, reducing the chance that it will reach threshold, and are thus _____.
The effect on the postsynaptic neuron depends on which _____ are activated.