Resumen de Electrical tweak lets worm grow two heads
The planarian flatworm is one of many creatures that have some kind of memory for lost limbs, enabling them to regenerate what was there before. Now it seems that this memory can be altered by meddling with the electrical activity of the animals' cells. Michael Levin at Tufts University in Medford MA and his colleagues have used anesthetic to shift the bioelectric current at the site of a cut, changing the type of appendage regenerated--allowing a head to be regrown in place of a tail. Charged ions constantly move in and out of cells, giving the cells an electrical charge. The patterns of electrical activity are thought to influence how embryos develop, but it's unclear how they work in adults.
