In a plant, a single locus affects both berry color and berry size.There are two mutant alleles (R₁ and R₂) in addition to the wild-type allele (R₀).Individuals that are R₀R₀ have large, white berries.Individuals that are R₁R₁ or R₀R₁ have red berries, individuals that are R₂R₂ or R₀R₂ have small berries, and R₁R₂ individuals have berries that are both red and small.What are the expected phenotypic ratios if you crossed R₁R₂ individuals to homozygous wild type? A) All would have small white berries. B) All would have large red berries. C) Half would have small white berries, and half would have large red berries. D) One-third would have wild-type berries, one-third would have small white berries, and one-third would have large red berries. E) One-quarter would have wild-type berries, one-half would have small white berries, and one-quarter would have large red berries.

Question

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The phenotype of the heterozygous parental crosses are R₁R₂ x R₀R₀. The Punnett square for this cross would be: | R₁ | R₂ --|----------------|---------------- R₀ | RrSs | RrSs R₀ | RrSs | RrSs Therefore, the expected phenotypic ratio is 1:1 for large red (RRss and Rrss) and small white (rrSS and rrSs) berries, resulting in half the offspring having small white berries, and half the offspring having large red berries.

In a Plant, a Single Locus Affects Both Berry Color