Tetrodotoxin, found in the tissues of puffer fish, binds specifically to voltage-gated Na channels and blocks their function. A few bites of poorly prepared puffer fish would cause… an increase in the firing of spontaneous action potentials. prolongation of action potential duration. hyperpolarization of nerve cells. depolarization of nerve cells. death by asphyxiation. Question 2 Multiple Choice 0.5 points Action potentials usually propagate in only one direction along an axon because… the refractory period prevents the immediate re-opening of voltage gated Na+ channels. both the voltage gated Na+ channels and K+ channels open only in one direction. the nodes of Ranvier conduct only in one direction. ions flow along the axon only in one direction. Question 3 Multiple Choice 0.5 points Which one of the following is a functional advantage of electrical synapses over chemical synapses? Electrical synapses are inherently unidirectional, insuring that postsynaptic
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This note was uploaded on 10/25/2010 for the course BISC 220L taught by Professor Herrera,mcclure during the Spring '07 term at USC.