spermatozoon

Mature and mobile reproductive male cell produced by the testicle; the main constituent of the sperm used to fertilize an egg.

head

Anterior section of the spermatozoon formed of a nucleus (organelle containing genetic information) and the acrosome (structure aiding in penetration of the egg).

middle piece

Part surrounding the base of the tail where the mitochondria, small organelles that supply the energy needed for the spermatozoon to move, concentrate.

neck

Narrow part connecting the head to the intermediary section; it contains the centrioles, structures that aid in cell division.

end piece

Terminal end of the spermatozoon’s tail.

tail

Filament whose oscillations enable the movement of the spermatozoon.