Question

The F₂ generation of a cross produced identical phenotypic and genotypic ratio. It is not an expected Mendelian result, and can be attributed to:
A. Independent assortment
B. Linkage
C. Incomplete dominance
D. None of the above

Answer 1

Hint: A type of intermediate inheritance known as incomplete dominance occurs when the effect of the dominant allele is diminished by the recessive allele. While the effects of the two alleles are blended, the dominant allele does not totally block the effects of the recessive allele.

Complete step by step solution:
The experiment he conducted on the Four o'clock bloom led German botanist Carl Correns to coin this phrase. A heterozygous person in this situation does not exhibit the effects of the dominant allele; instead, the phenotypes of the dominant and recessive alleles are combined, and they exhibit an intermediate of both phenotypes. Because the dominant allele does not entirely suppress the recessive allele, this phenomenon is also known as partial dominance, semi-dominance, or intermediate inheritance. Due to the co-expression of two alleles, heterozygosity is crucial for the research of genes.
The ABO blood type system in humans, human hair patterns (curly or wavy), the colour of the blossom in roses and Mirabilis jalapa, etc. are some well-known examples of this inheritance.
Due to this imperfecta inheritance pattern, the phenotypic ratio in the F2 generation is different from the original ratio. A Punnett square can be used to clarify this situation.
This has a 1:2:1 genotypic to phenotypic ratio, which is identical to the genotypic ratio. In the ratio, the first number represents the dominant trait and the last number represents the recessive trait. The result of merging the two alleles is represented by the middle number. In the F2 generation, the typical phenotypic ratio is 3:1 and the genotypic ratio is 1:2:1.
Hence, the correct option is C. Incomplete dominance

Note:
The phenomenon of incomplete dominance occurs when the dominant allele does not fully express itself. The four o'clock or Mirabilis jalapa plant's flowers were the first to be examined for this occurrence. In F2 generation in imperfect dominance, the phenotypic and genotypic monohybrid ratio is 1: 2: 1, or pure dominant: hybrid: pure recessive.