User:YungBenny/sandbox
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Test Cross (Article title)
Under the law of dominance in genetics, an individual expressing a dominant phenotype could contain either two copies of the dominant allele (homozygous dominant) or one copy of each dominant and recessive allele (heterozygous dominant).[1] By performing a test cross, one can determine whether the individual is homozygous or heterozygous dominant.[1]
In a test cross, the individual in question is bred with another individual that is homozygous for the recessive trait and the offspring of the test cross are examined[2]. Since the homozygous recessive individual can only pass on recessive alleles, the allele the individual in question passes on determines the phenotype of the offspring.[3] Thus, this test yields 2 possible situations: