What fraction of the F2 generation will display both dominate traits?
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Answer:
B. 9 out of 16 will display both dominant traits.
Explanation:
Based on the scenario, we know that the genotypes of the F1 generation would be all Heterozygous for both traits.
Let us assign the following:
R is to Round
r is to wrinkled
Y is to Yellow
y is to green
So the genotypes of both parents would be:
RrYy
Look at the attached to see the resulting Punnett. For the dominant traits to be expressed, the traits should have at least 1 dominant allele. So you are looking for out comes with the following Genotypes:
RRYY
RrYY
RRYy
RrYy
This is because the dominant trait masks the recessive, so you need at least 1. The second picture attached is the results of the frequencies.
So counting it, you would have 9 out of 16 outcomes that display both dominant traits.