Stem cells use signal orientation to guide division, study shows

A signal from one direction may cause a cell to react in a very different way than if it had come from another direction.

http://www.sciencedaily.com/releases/2013/03/130321141446.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily%2Fplants_animals%2Fbiotechnology+%28ScienceDaily%3A+Plants+%26+Animals+News+--+Biotechnology%29