All the offspring of a cross between a black-eyed mendelian and an orange-eyed mendelian have black eyes. what is the expected phenotypic ratio of a cross between two orange-eyed mendelian? a.3 black-eyed: 1 orange-eyed b.0 black-eyed: 1 orange-eyed c.1 black-eyed: 3 orange-eyed d.1 black-eyed: 0 orange-eyed

The answer is B. The first cross between the black-eyed mendelian and an orange-eyed mendelian resulted in all of them having black eyes. This means that black-eyed is the dominant trait in the species. That means if a phenotype is orange-eyed then it is homozygous recessive (bb). There will be no black-eyed since all of them are recessive.

A: rachel carson :