Question

why is human male called heterogametic??

Answer 1

Heterogametic refers to the males which produce dissimilar gametes, such as those of human males, who produce two types of spermatozoa or gametes, one bearing the X-chromosome and the other bearing the Y-chromosome.

Answer 2

Hetero gametic  (di gametic ) refers to the  of a species in which the chromosomes are not the same. For example, in humans, males, with an X and a Y  chromosome, would be referred to as the hetero gametic , and females having two X  chromosomes would be referred to as the homo gametic