Pairs of homologous chromosomes code for the same genes (in the same order), but may or may not contain the same alleles. For example, one chromosome may have the following sequence: A-b-C-D-eand the other: a-B-c-d-eThese chromosomes are homologous because they contain the same genes (a, b, c, d, e), but have some differing alleles. Hope this helps: D