Arcs

... arm or leg jerks upwards). Only three nerve cells are involved, and the brain is only aware of the response after it has taken place. Such reflex arcs are particularly common in animals, and have a high survival value, enabling organisms to take rapid action to avoid potential danger. Conditioned ...

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... Ehrenhaft since the 1930’s and by Mikhailov since the 1980’s involved particles created by the sputtering of ferromagnetic materials in electrical arcs, while those recently observed by Urutskoev et al. were produced in exploding discharges (titaniumsheets in water) and only later bound themselves ...

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jaws are thought to have evolved from the brancial arcs.

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