Spontaneous symmetry breaking and motility initiation of keratocytes. Phase-contrast time-lapse video of a keratocyte spontaneously breaking symmetry and initiating motility. The cell has been reoriented such that the eventual direction of movement is to the right. 50x real time (frames were collected at 5-s intervals and are displayed at 10 frames/s). Corresponds to Fig. 2 A (cell A).
