Physiology 1021 Lecture Notes - Myelin, Axon Terminal, Multiple Sclerosis

• School: Western University
• Department: Physiology
• Course: Physiology 1021
• Professor: John Ciriello

Document Summary

Dendrite: hair-like structures at the end of a neuron that receive incoming signals & communicate with other neurons. Cell body(soma): control centre of the cell, contains the nucleus y and all necessary organelles for directing cellular activity. Axon hillock: point at which the action potential begins its generation in the cell, specialized region from where axon projects. Collaterals: branching of axon near terminal end, serve to increase # of possible target cells with which a neuron can interact. Terminal bouton/axon terminal: swelling at the end of axon collateral, containing mitochondria & membrane-bound vesicles containing various neurochrine molecules y chemicals in axon terminal facilitate transmission of the signal across the synapse to target cell. Hyperpolarization y after this negative phase the membrane potential returns to the resting levels of -70mv. Voltage-gated channels: y voltage-gated sodium & voltage-gated potassium channels y. Voltage-gated sodium channels: y only allows na+ through y gates open only when their is a depolarization.