A closer look at what makes up the human genome...
OK, so what are homologous chromosomes?
The human genome (Figure B-10) is composed of 23 kinds of chromosomes. However, because humans conceive through sexual reproduction, every child receives two sets of 23 chromosomes – one from his or her mother and one from his or her father. As a result, every individual has 23 pairs of chromosomes, for a total of 46. Of these 23 pairs, one pair is responsible for determining sex. The chromosomes in this pair are therefore called sex chromosomes. The chromosomes in the remaining 22 pairs are called autosomes.
The two chromosomes in a pair of autosomes are called homologues, or a “homologous pair,” meaning that they contain corresponding sequences of DNA (Figure B-11). These two chromosomes come from separate parents. Don’t be misled; homologous chromosomes contain DNA sequences that are similar, but they are not identical copies of each other!
Last Modified: 7-15-03
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The human genome (Figure B-10) is composed of 23 kinds of chromosomes. However, because humans conceive through sexual reproduction, every child receives two sets of 23 chromosomes – one from his or her mother and one from his or her father. As a result, every individual has 23 pairs of chromosomes, for a total of 46. Of these 23 pairs, one pair is responsible for determining sex. The chromosomes in this pair are therefore called 
