PHY100H1 Lecture Notes - Lecture 5: Axon Hillock, Efferent Nerve Fiber, Depolarization
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PHY100H1 Full Course Notes
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Graded potentials are variable strength signals that travel over short distances and lose strength as they travel through the cell. If a depolarizing graded potential is strong enough when it reaches integrating region within a neuron the graded potential initiates an action potential. Graded potential reflects stimulus strength: graded potentials in neurons are depolarizations or hyperpolarizations that occur in the dendrites and cell body or less frequently near the axon terminals. Graded because their size or amplitude is directly proportional to the strength of the trigger events: the wave of depolarization that moves through the cell is known as local. If more na+ channels open more na+ enters, and the graded potential has a higher initial amplitude: why do graded potentials lose strength as they move through. Grade potentials that are strong enough eventually reach the region known as the trigger zone. Na+ and k+ moves across the membrane during aps.
