No, not all cells move; those that do move (or are motile) have distinct body features and methods for moving about. The two main features that help various types of cells move are cilia and flagella. Both have the same internal structure, but differ in their length, the number occurring per cell, and mode of beating. Cilia are about 2 to 10 microns (MGR) long, while flagella are much longer, ranging from 0.0394 microns to just under an inch (1 millimeter to several millimeters) long, although they are most commonly 10 to 200 microns (MGR) long. Both cilia and flagella are used by cells to move through watery environments or to move materials across cell surfaces. Cilia move back and forth, while flagella undulate in a whiplike motion, moving in the same direction as their axis.