Question

Mrs Kim planted blue and white flowers if next year she has pale blue flowers what has most likely happened if the flowers self pollinate what will happen with the f2 generation

Answer 1

Answer:

1. Incomplete dominance has occurred

2. A phenotypic ratio 1 Blue : 2 pale blue : 1 white will be obtained.

Explanation:

Mendelian principle states that one allele is capable of masking the expression of another i.e. one allele is dominant and the other one is recessive. Genetic scenarios that have gone against this principle has been observed. One of them is the concept of INCOMPLETE DOMINANCE, which is a case where one allele is not completely dominant over the other, hence, they combine to form a third intermediate phenotype different from both parents.

This is the case in the question where the the blue allele (B) fails to completely dominate the white allele (W), instead it forms an heterozygous plant (BW) with a different phenotype (pale blue) that is a blending of the two parental phenotypes (blue and white). This heterozygote (BW) is formed in the F1 generation.

If the F1 offsprings (BW) are self-crossed, four possible offsprings will be produced using a punnet square. This offsprings will have genotypes: BB, BW, BW, and WW. This depicts a genotypic and phenotypic ratio of 1:2:1 i.e. 1 blue (BB) : 2 pale blue (BW) : 1 white (WW).