Finding their sense of direction: Cell movement helps tissues establish polarity

From the hairs on our arms to the microscopic sensory structures of the inner ear, many tissues in the body are built with a clear sense of direction. To build these structures throughout development, individual cells must establish which way they are facing—and coordinate that orientation with cells around them. If they get this wrong, tissues may fail to form, form improperly or fail to function.

Source: Phys.org