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Crossing over is thought to be evolutionarily advantageous because it continually shuffles genetic alleles into novel combinations. Until recently, it was thought that Y-linked genes might degenerate because they lack homologous genes on the X chromosome with which to recombine. However, when the Y chromosome was sequenced, eight large regions were found to be internally homologous to each other, and quite a few of the 78 genes represent duplicates. Explain how this might be beneficial.
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- 14arrow_forwardNonearrow_forwardCan simple translocations ever be balanced? I know with reciprocal translocations that if you're swapping the same *amount* of genetic material, it would be balanced, but if not, it would probably be unbalanced. (I'm referring to the genetic material of each chromosome, and not the total genetic material). But simple translocations on the other hand, you're adding part of a chromosome to another without swapping. So it's not possible to have a balanced simple translocation, correct?arrow_forward
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