Final answer:
Cilia on sperm beat in a direction that propels the sperm forward, helping them swim towards the egg for fertilization.
Step-by-step explanation:
Cilia are microscopic extensions of the apical cell membrane that are supported by microtubules. They beat in unison and move fluids as well as trapped particles. In the case of sperm, the cilia beat in a direction that propels the sperm forward. This movement helps the sperm swim towards the egg for fertilization.