Answer:
motor proteins
Explanation:
Cell motility is one of the crowning achievements in evolution. It is vital for both normal biology and in disease.
It involves the action of cytoskeleton and motor protein.
The cytoskeleton unlike passive networks can undergo rearrangements which can produce movement.
Motor proteins use ATP to 'walk' or slide across  microfilament or microtubule.
Some movements require the action of both the motor proteins and cytoskeleton rearrangements.