ANP 1105 Lecture Notes - Lecture 5: Myelin, Schwann Cell, Urinary Incontinence

• School: University of Ottawa
• Department: Anatomy and Physiology
• Course: ANP 1105
• Professor: Joanne Savory

Document Summary

7: action potentials, depolarization increases the probability of producing nerve impulses, hyperpolarization decreases this probability, graded potentials, short-lived depolarizations or hyperpolarizations current decreases with distance traveled, graded because magnitude determined by strength of stimulus. Initial stimulus depolarizes or hyperpolarizes local area of membrane: decremental movement of ions on either side of membrane propagates signal for short distance. Na+ channels close, k+ channels open - 7 junction between 2 neurons or neuron + effector: the synapse, presynaptic vs postsynaptic neuron (most neurons are both, 2 types of synapses: electrical and chemical, a. function to open or close ion channels that in uence membrane permeability and, consequently, membrane: b. Because receptors only on the dendrites not the axon terminals: mechanism of synaptic communication initiation, 1. Ca++ gates open in presynaptic terminal: 2. More na movement than k: what is generated is not an ap; only axonal membranes can generate.