Mendels laws

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Mendel's laws Two general laws of inheritance formulated by the Austrian monk GregorMendel. Re-expressed in modern terms, the first law, of segregation, is that the two members of a gene pair segregate from each other during meiosis, each gamete having an equal probability of obtaining either member of the gene pair. Re-expressed in modern terms, the second law, of independent assortment, is that different segregating gene pairs behave independently. This second law is not universal, as was originally thought, but applies only to unlinked or distantly linked pairs (see linkage). At the time of Mendel, genes had not been identified as the units of inheritance: he considered factors of a pair of characters segregating and members of different pairs of factors assorting independently.