The figure below shows three generations in one of Mendel's experiments and demonstrates that purple flower color is dominant over white flower color in peas. Which of the following is the best rationale for this conclusion?
A)In the F2 generation, more plants have purple flowers. In any cross, the allele that is most common in the offspring is dominant.
B)Members of the F1 generation are heterozygous. Whatever allele is visible in a known heterozygote is considered dominant.
C)The stronger, or in this case, darker, allele is always considered dominant.
D)An individual that produces more offspring gives more alleles to the next generation. As a result, that allele dominates the next generation.

Question

The figure below shows three generations in one of Mendel's experiments and demonstrates that purple flower color is dominant over white flower color in peas. Which of the following is the best rationale for this conclusion? 
A)In the F2 generation, more plants have purple flowers. In any cross, the allele that is most common in the offspring is dominant. 
B)Members of the F1 generation are heterozygous. Whatever allele is visible in a known heterozygote is considered dominant. 
C)The stronger, or in this case, darker, allele is always considered dominant. 
D)An individual that produces more offspring gives more alleles to the next generation. As a result, that allele dominates the next generation.

Quizplus · Accepted Answer

The rationale for concluding that purple flower color is dominant over white flower color is that the members of the F1 generation are heterozygous, and whatever allele is visible in a known heterozygote is considered dominant. In this case, all F1 plants had purple flowers even though they carried the allele for white flowers. Therefore, purple flower color is dominant over white flower color in this experiment.

The Figure Below Shows Three Generations in One of Mendel's