Biology. Male reproductive cell (gamete) which can fertilize a female's egg. A sperm cell has only a haploid chromosome set necessary for producing an embryo, the other half is supplied by the female egg cell.
The matured human spermatozoon is about 60 µm long and consists of a head, a neck, a middle piece, and a long tail (flagellum) by which it propels itself with a vigorous lashing movement. The head contains the cell nucleus with the haploid chromosome set. The head is covered by the acrosome which contains enzymes used for penetrating the female egg. The neck contains the centrioles which are involved in the division of the chromosomes in the fertilized egg.
The middle piece contains many spirally arranged mitchondria which provide ATP as energy for the sperm mobility. The tail executes lashing movements that propel the spermatozoon. Microtubules in the middle piece and parts of the tail enable the motion of the tail.