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Propagation speed of action potential

Range	<=1 unmyelinated axon: 50 to 100 myelinated axon m/sec
Organism	Various
Reference	Zalc B. The acquisition of myelin: a success story. Novartis Found Symp. 2006 276: 15-21 discussion 21-5, 54-7, 275-81. p.16 top paragraphPubMed ID16805421
Comments	Invertebrate axons are ensheathed by glial cells, but do not have a compact myelin. As a consequence, action potentials along invertebrate axons propagate at about 1 m/s, or less. Cephalopods have increased the width of the axon thus achieving greater speeds without myelin. For speed between 1 and 120m/sec see Eastern Kentucky University human physiology notes under "conduction velocity" link
Entered by	Uri M
ID	107125