What percentage of GREEN offspring did the Yy parents have?
A. 2 out of 4, 50%
B. 3 out of 4, 75%
C. 1 out of 4, 25%
D. 0 out of 4, 0%
The correct answer is C. 1 out of 4, 25%.
In this case, Y represents the dominant allele for yellow, and y represents the recessive allele for green. Since one parent has the Yy genotype, it means that it is heterozygous for the trait. This means that it has one dominant allele (Y) and one recessive allele (y).
When the two parents with the Yy genotype are crossed, they can produce four possible combinations of alleles in the offspring: YY, Yy, Yy, and yy.
Out of these four possibilities, only one combination (yy) will result in a green phenotype. Therefore, the Yy parents have a 25% chance of producing green offspring.