Initiated at the hillock propagate toward the axon

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Unformatted text preview: e a series of action potentials propagated in sequence down the neuron. • Only the axons of neurons conduct the nerve impulse. • Initiated at the hillock, • Propagate toward the axon terminus Heyer 4 Coordination of Body Functions How can conduction rate be increased? How can conduction rate be increased? 2. Myelinated axons — vertebrates only! 1. Increase diameter of the axon. • Increase diffusion rate of cations down through the axon. • “Giant axons ” of cephalopod molluscs and crustacean arthropods may be 1mm in diameter and have a conduction speed of 100m/sec. Transmission: Synapses & Local Signaling • Synaptic terminals release a neurotransmitter. – e.g. acetylcholine • NT binds to receptors on postsynaptic cell. Glands: organs specialized for secretion Formation o f E pithelial G lands • Saltatory conduction : 25 µm myelinated vertebrate neuron may have conduction rate of 120 m/sec. Transmission of the signals: the Synapse • Synapse: functional connection between a neuron...
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This note was uploaded on 09/02/2011 for the course BIOL 6a taught by Professor Staff during the Fall '10 term at DeAnza College.

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