Radish flowers may be red,purple,or white.A cross between a red-flowered plant and a white-flowered plant yields all-purple offspring.The part of the radish we eat may be oval or long,with long being the dominant trait.If true-breeding red-flowered long radishes are crossed with true-breeding white-flowered oval radishes,the F₁ will be expected to be which of the following?

Question

Quizplus · Accepted Answer

The cross between true-breeding red-flowered long radishes and true-breeding white-flowered oval radishes can be represented as: RrLL x rrbb where R represents the dominant allele for red flowers, r represents the recessive allele for white flowers, L represents the dominant allele for long radishes, and b represents the recessive allele for oval radishes. The F1 generation will all be RrLl, meaning they will all have purple flowers (from the cross between red-flowered and white-flowered parents) and be long (from the dominance of the long trait). When these F1 plants are self-crossed, the expected ratio of offspring is 9:3:3:1. This means that 9/16 of the offspring will be purple and long (RrLl), 3/16 will be red and long (Rrll), 3/16 will be white and oval (rrbb), and 1/16 will be white and long (rrLl). Therefore, the expected outcome for the F₁ is purple-flowered and long.

Radish Flowers May Be Red,purple,or White