Answer:
heterologous
Explanation:
Recombination occurs between homologous regions between chromosomes.
Although sex chromosomes come from autosomal chromosomes and were once homologous, they have evolved distinctly casuing low homology between them. Currently sex chromosomes are heterologous and differ substantially in composition. In fact, recombination between sex chromosomes only occurs in a small pseudoautosomal region that is still homologous.
