HEREDITY
MONOHYBRID CROSS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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2:4 PP 2:4 Pp4:4 white
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2:4 PP 2:4 Pp4:4 purple
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1:4 PP 2:4 Pp 1:4 pp3:4 purple 1:4 white
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2:4 PP 2:4 pp2:4 purple 2:4 white
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Detailed explanation-1: -P is dominant to p, so offspring with either the PP or Pp genotype will have the purple-flower phenotype. Only offspring with the pp genotype will have the white-flower phenotype.
Detailed explanation-2: -The F2 generation is 25% PP (homozygous dominant, purple flowers), 50% Pp (heterozygous, purple flowers), and 25% pp (homozygous recessive, white flowers). This is how the white characteristic reappears in the second generation. The phenotype is 3:1, purple to white.
Detailed explanation-3: -Upon self-pollination of F1 progeny, purple flowered and white flowered plants are produced in a 3:1 ratio.
Detailed explanation-4: -There was a 3:1 ratio of purple:white flowers in generation F2 because the “masked” (recessive) genes from the F1 generation were allowed to pair, however they were only allowed to pair one time leaving the other three times to appear with purple flowers.