Homologous chromosome
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Two chromosomes are said to be homologous when they have the same loci in the same positions for all the genes they contain, besides being of the same length. They can only be accounted for in diploid, such as humans, or polyploid beings. Each homologous chromosome is inherited from a different parent (i.e., one from the mother and one from the father), for example the 46 human chromosomes are in fact 23 homologous pairs of chromosomes, 23 inherited from the mother and 23 from the father (see karyotype for an picture of the 23 pairs of chromosomes). It contains information about the same gene sequence. Homologous chromosomes are all similar in length, except for sex chromosomes in several taxa, where yhe X chromosome is longer than the Y chromosome; this is because these choromosomes only share a small region of homology.
Not to be confused with sister chromatids. Template:Biosci-stub