Differences between Graded Potential and an Action Potential
Cannot be summed
Action Potential
Amplitude varies with size of initiating event
Graded Potential
All or none: Once membrane is depolarized to threshold, amplitude is independent of the size of the initiating event
Action Potential
Duration is constant for a given cell type under constant conditions
Action Potential
Has a refractory period
Action Potential
Initiated only by a graded potential
Action Potential
Is conducted without decrement, the depolarization is amplified to a constant value at each point along the membrane
Action Potential
Mechanism depends on voltage gated channels
Action Potential
Amplitude decreased with distance
Graded Potential
Can be summed
Graded Potential
Duration varies with initiating event
Graded Potential
Has no refractory period
Graded Potential
Initiated by environmental stimulus, NT, or spontaneously
Graded Potential
Mechanism depends on ligand gated or other chemical or physical changes
Graded Potential
Can be a depolarization or a hyper polarization
Is only a a depolarization