The Origin of Random Forces Inside Cells

Place yourself in a bumper car at a carnival waiting to bump into your friends. Soon enough you hear the small engine of your bumper car start and you begin to move around, bumping into anyone in your way. While the motion of your car is mostly controlled by the steering wheel, random events---like fluctuations in the motor power, your car hitting small bumps on the floor, and other cars hitting you---can affect the motion as well. What if I told you that a cell and its parts function in a similar way? Just as your car is powered by electricity, molecular motors---bio-molecules that can convert chemical energy into mechanical work---power the movement of living organisms by generating forces. In order to produce these forces, molecular motors depend on an organic molecule called ATP.