The head of the sperm includes the acrosome and the nucleus.
The sperm head contains an elongated haploid nucleus, the anterior portion of which is covered by a cap-like structure, acrosome.
The acrosome is filled with digestive enzymes that help fertilisation of the ovum. In other words when the sperm encounters the egg, digestive enzymes will digest the oocyte membrane and allow the nucleus of the sperm to penetrate.