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In the datura plant, purple flower color is controlled by a dominant allele P. White flowers are found in plants homozygous for the recessive allele p. Suppose that a purple-flowered datura plant with an unknown genotype is self-fertilized and that its progeny are 28 purple-flowered plants and 10 white-flowered plants.
a. Use the results of the self-fertilization to determine the genotype of the original purple-flowered plant.
b. If one of the purple-flowered progeny plants is selected at random and self-fertilized, what is the probability it will breed true?
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