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Do the genes of the X and Y chromosomes determine only sex characteristics ? / Does the...
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The XY chromosome pair determines sex--XX is a female and XY is a male. However, the X chromosome is slightly longer than the Y and contains more genes along its length. Therefore, there are traits known as sex-linked and most of these are found along the X chromosome. An example is red-green colorblindness and another is Hemophilia(bleeder's disease). Since males only have one X chromosome which is passed down from mother to son and if they get an X with the disease gene, then they will express a disease phenotype. Since females have two X chromosomes, if one is normal and the other contains the recessive gene for the disease, they will be carriers and express a normal phenotype. There are also approximately 3 dozen Y-linked genes. These only affect males and relate to male sexual characteristics as well as infertility. These are only passed from father to son.
Posted by trophyhunter1 on December 24, 2012 at 2:12 PM (Answer #2)
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