In grasshopper, the mechanism of sex determination is of the XO type. In females, the eggs bear a pair of X chromosomes along with the autosomes. On the other hand, there are two types of sperms formed in males–one having a X chromosome and other having no chromosome. Hence, grasshopper shows male heterogamety.
In Drosophila, the mechanism of sex determination is of XY type. Females have a pair of X chromosomes, while the males have two types of sperms–one having X chromosome and other having Y chromosome.
XX – XY type:
