Understanding Action Potentials and their Role in the Nervous System, Study notes of Histology

Download Understanding Action Potentials and their Role in the Nervous System and more Study notes Histology in PDF only on Docsity! The Nervous System Action potentials Jennifer Carbrey Ph.D. Department of Cell Biology Cell types neurons glial cells Methods of communication in nervous system – action potentials How the nervous system is organized central vs. peripheral Nervous System Action potentials move one-way along the axon because of the absolute refractory period of the voltage gated Na+ channel. Unidirectional Propagation of AP image by Rick Melges, Duke University Input: Dendrites: ligand gated ion channels, some voltage gated channels; graded potentials Cell body (Soma): ligand gated ion channels; graded potentials Output: Axon: voltage gated ion channels, action potentials Axon initial segment: highest density of voltage gated ion channels & lowest threshold for initiating an action potential, “integrative zone” Integration of Signals Axon Initial Segment Integration of signals at initial segment image by Rick Melges, Duke University