PHGY 209 Lecture Notes - Lecture 4: Squid Giant Axon, Saltatory Conduction, Schwann Cell
13 Dec 2017
School
Department
Course
Professor
Document Summary
When you burn yourself you first feel a sharp pain as you remove your hand from the surface. After (cid:1005) or (cid:1006) se(cid:272)o(cid:374)ds you start to feel a (cid:373)ore (cid:862)(cid:271)ur(cid:374)i(cid:374)g(cid:863) pai(cid:374). This (cid:862)slo(cid:449) pai(cid:374)(cid:863) is propagated (cid:271)y affere(cid:374)ts (cid:272)alled (cid:862)c fi(cid:271)ers(cid:863) The propagation of action potentials is fast, but it has its limitations. The goal is to propagate the action potential as fast as possible! The one who does it wins in natural selection. One way to make action potentials to propagate faster is to increase the diameter of the axons. Squid giant axon = giant axon that goes in the middle of a squid. Was used to study the action potentials, and it is a very good example of evolution making the action potentials travel faster. The mammalian axon cannot be that big to fit on the organism. The solution nature found it to insulate the axon. Myelin wraps around the axon to insulate it.
