<P> Graded potentials are changes in membrane potential that vary in size , as opposed to being all - or - none . They arise from the summation of the individual actions of ligand - gated ion channel proteins , and decrease over time and space . They do not typically involve voltage - gated sodium and potassium channels . These impulses are incremental and may be excitatory or inhibitory . They occur at the postsynaptic dendrite as a result of presynaptic neuron firing and release of neurotransmitter , or may occur in skeletal , smooth , or cardiac muscle in response to nerve input . The magnitude of a graded potential is determined by the strength of the stimulus . </P>
<P> Graded potentials are changes in membrane potential that vary in size , as opposed to being all - or - none . They arise from the summation of the individual actions of ligand - gated ion channel proteins , and decrease over time and space . They do not typically involve voltage - gated sodium and potassium channels . These impulses are incremental and may be excitatory or inhibitory . They occur at the postsynaptic dendrite as a result of presynaptic neuron firing and release of neurotransmitter , or may occur in skeletal , smooth , or cardiac muscle in response to nerve input . The magnitude of a graded potential is determined by the strength of the stimulus . </P>
where are graded potentials generated in nerve cells
where are graded potentials generated in nerve cells
the postsynaptic dendrite
the postsynaptic dendrite