HEREDITY
MONOHYBRID CROSS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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50%Rr & 50%Rr (genotype) and 100%Round (phenotype)
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100%RR & 100%RR (genotype) and 100%Round (phenotype)
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50%Rr & 50%rr (genotype) and 50%Round & 50%Wrinkled (phenotype)
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100%rr & 100%rr (genotype) and 100%Wrinkled (phenotype)
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Detailed explanation-1: -Based on this observation round seeds is the dominant phenotype. With dominant being round seeds that would mean wrinkle seeds are the recessive trait. Therefore a cross of heterozygous for round with a homozygous recessive for wrinkled, will yield an F1 generation that has 50% round seeds and 50% wrinkle seeds.
Detailed explanation-2: -In the F1 generation, 50% of the offspring produced wrinkled seeds.
Detailed explanation-3: -In pea plants, round seeds are dominant and wrinkled seeds are recessive. A pea plant with round seeds was pollinated with a pea plant with wrinkled seeds. The offspring produced round seeds. One of the offspring was mated with a pea plant with heterozygous genes for round seeds.
Detailed explanation-4: -So, the wrinkled phenotype of pea seed is given by double recessive ‘rr’ genotype.