Homologous chromosomes do not necessarily have to have exactly the same type of alleles.
<em>Homologous chromosomes consist of a pair of chromatids with the same length, centromere position, and more or less the same gene. However, the gene can have the same or different alleles, meaning that the genes can be expressed differently in individuals. Dominant alleles are usually expressed while recessive alleles remain in the background. </em>
