what event triggers the generation of an action potential?
Generation of an Action Potential Across. Sarcolemma. Resting sarcolemma is polarized. Opening chemically gated ion channels upon ACh binding to ACh receptors allows. Na+ & K+ to pass the sarcolemma. More Na+ in than K+ out depolarization (interior slightly less negative.
A stimulus is received by the dendrites of a nerve cell. This causes the Na+ channels to open. If the opening is sufficient to drive the interior potential from -70 mV up to -55 mV, the process continues. Having reached the action threshold, more Na+ channels (sometimes called voltage-gated channels) open.