PHYS 215 Lecture 10: Lecture 10 - PHYS 215
31 Dec 2018
School
Department
Course
Professor
Document Summary
What is synaptic transmission: how an ap is transmitted from one neuron to another neuron. Exocytosis: vesicular transport that extrudes large molecules from the cell, requires atp and ca. If chemically-operated na+ channels open, increase in p-na: called an epsp (excitatory postsynaptic potential) If chemically-operated k+ channels open, increase in p-k: called an ipsp (inhibitory postsynaptic potential) It is removed from the synaptic cleft by uptake by the presynaptic neuron or breakdown by the postsynaptic neuron. What are the two kinds of synapses: epsp = small depolarization of the vm towards the threshold potential, due to increase p-na and decrease p-k. Ipsp = small hyperpolarization of vm away from the threshold potential. Can a postsynaptic neuron receive both epsp and ipsp from presynaptic neurons: yes (convergence, whether it is an epsp or an ipsp depends on the neurotransmitter. How many epsp must be received to depolarize the postsynaptic neuron to threshold: approximately 50 more epsp than ipsp.
