The term heterogametic refers to when the sex chromosomes are non-uniform, in other words they are not the same chromosome.
Examples in Nature
The heterogametic sex in Homo sapiens is male (XY). We can use modes of sex determination to understand more about heterogametic sexes. The Protenor mode of sex determination expresses this as XO where the Lygaeus mode of sex determination displays this as XY. In some species like chickens and in moths the heterogametic sex in the female. In this situation biologists use the expression ZW to express the heterogametic sex .
- ↑ Hartl et. al (2012) Genetics: Analysis of Genes and Genomes, page 132, 8th Edition,Burlington,MA: Jame and Barlett Learning