A pair of chromosomes is called a homolgous pair or homologue . One member of the homologous pair comes from each parent. Each set carries information about the same traits in the same sequence, but the content of the information in each set may be different. That is, each set carry genes which determine a certain trait, but the genes you get from your mother may give you one version of that trait, whereas the genes you get from your father may give you the another version. Genes for the same trait on a homologous pair of chromosomes are called alleles .
Autosomes are chromosomes that carry information for non-sex characteristics.
The remaining 1 pair are called the sex chromosomes , which carry sex linked genes and dertemine an individual's sex. These chromosomes are labeled XX in the female and XY in the male. This cell division segregates the two chromosomes of each homologous pair and reduces the chromosome number by one-half. This is a longer and more complex process than prophase of mitosis. Crossing over - the exchange of chromosome segments between homologues.