GENETICS AND EVOLUTION
EVOLUTION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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mostly white
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75% purple; 25% white
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all purple
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50% purple; 50% white
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Detailed explanation-1: -In the pea plant, purple colour of flower is dominant over white colour. Progeny obtained by crossing pure purple flowered plants with white flowered plants are self-pollinated.
Detailed explanation-2: -Only offspring with the pp genotype will have the white-flower phenotype. Therefore, in this cross, you would expect three out of four (75 percent) of the offspring to have purple flowers and one out of four (25 percent) to have white flowers. These are the same percentages that Mendel got in his first experiment.
Detailed explanation-3: -Answer and Explanation: In this situation, every offspring produced from this cross with be a heterozygote (Pp), and because purple is dominant to white, all the offspring will be purple. Therefore, the probability of an offspring having white flowers is zero.
Detailed explanation-4: -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.