het·er·o·ga·met·ic 
(hĕt′ə-rō-gə-mĕtĭk)
(hĕt′ə-rō-gə-mĕtĭk)adj.
1. Producing dissimilar gametes, such as those of human males, who produce two types of spermatozoa, one bearing the X chromosome and the other bearing the Y chromosome.
2. Of or relating to heterogametes.