OBJECTIVE LIFE SCIENCE
GENETICS
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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the allele for tallness is dominant
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they inherited an allele for shortness and tallness from each parent
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the allele for shortness is lost
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the F1 generation plants that were crossed to make the F2 plants were all heterozygous
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Detailed explanation-1: -When a tall and short plant are crossed, all of the offspring are tall. If the offspring self-fertilize, they produce tall and short plants in a ratio of 3:1 in the next generation. Mendel’s actual counts were 787 tall:277 short plants in this generation (2.84:1 ratio).
Detailed explanation-2: -Mendel crossed true breeding tall plant with true breeding dwarf plant and raised F2 generation from F1hybrid. Mendel observed that out of the 1064 F2 prophecies, 787 were tall. And 277 were dwarf. how many plants were expected to be in heterozygous condition?
Detailed explanation-3: -A cross between pure breeding tall (TT) and dwarf (tt) plants produce all tall (Tt) plants in F1 progeny. These heterozygous tall plants produce 50% gametes with “T” allele and 50% with “t” allele. Random fusion of these gametes from two heterozygous tall plants gives tall and dwarf plants in 3:1 ratio.