Multiple alleles Transitional Reasoning Download PDF

Questions

1. 1.

   In a diploid species of clover, leaf markings are determined by a single autosomal gene with four alleles exhibiting a strict dominance hierarchy: $M_1 > M_2 > M_3 > M_4$. A botanist crosses a plant displaying the $M_2$ phenotype with another plant displaying the $M_3$ phenotype, and among the resulting progeny, some exhibit the fully recessive $M_4$ pattern. Based on the principles of multiple allelism, which statement correctly identifies the parental genotypes and the expected phenotypic ratio of their offspring?

   • A) The parents are $M_2 M_3$ and $M_3 M_4$, producing offspring with a phenotypic ratio of 3 $M_2$ : 1 $M_4$.
   • B) The parents are $M_2 M_2$ and $M_3 M_4$, producing offspring with an equal phenotypic ratio of 1 $M_2$ : 1 $M_3$.
   • C) The parents are $M_2 M_4$ and $M_3 M_4$, producing offspring with a phenotypic ratio of 2 $M_2$ : 1 $M_3$ : 1 $M_4$.
   • D) The parents are $M_2 M_4$ and $M_3 M_3$, producing offspring with an equal phenotypic ratio of 1 $M_2$ : 1 $M_3$.