PSYC 101 Lecture Notes - Lecture 18: Myelin, Nicotine, Reuptake
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PSYC 101 Full Course Notes
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Psyc 101 week 7 lecture 1: biological psychology. Parts of the neuron: dendrites (1) Receives information from other cells: soma (2) Can be very short or over 1 m long. Myelin (sheaths) fatty coating over some parts of the axon. Speeds up the rate of transmission (0. 5-10m/s up to 150m/s) Nodes of ranvier gaps between myelin: terminal buttons (3) Resting state higher concentration of na+ outside and higher concentration of k+ inside. Action potential neuron gets a signal to fire and na+ goes in from the channel so there is a net positive charge. Then, k+ ions are pumped out to balance out the concentration gradient: passes down the axon in a sequence, either happens or does not happen (all-or-nothing) 2: absolute refractory period it is impossible to fire while it is returning to rest, relative refractory period it is possible for it to fire again but it would require much more stimulus.
