Spermatozoa

 Spermaotozoa (singular: spermatozoon) are mature male germ cells. It is originated in the male testes and is fertilized by the ovum. This fertilzation occurs during sexual reproduction. Spermatozoon is produced by the male body from adoloscence till death, whereas female ovum stops being made by the female body after a point in their life. The spermatoza are shaped like tadpoles, which contain a head, a center region, and a tail. 

An organelle, known as the acrosome, forms in the head of the spermatozoon and that contains a digestive enzyme. This enzyme helps the sperm break, or digest, through the outer membrane of the ovum. By this, the haploid nucleas is able to unite with the haploid nucleas  of the ovum. After that germination occurs.

Reference: 

https://medical-dictionary.thefreedictionary.com/spermatozoa

https://en.wikipedia.org/wiki/Acrosome