Question

Suppose you cross a homozygous blue flower with a homozygous yellow flower. In the next generation, all of the flowers are blue. What does this outcome tell you about the allele for blue flowers?

A: The blue allele is sex-linked.

B: The blue allele is dominant to the yellow allele.

C: is crossed out

D: The blue allele is co-dominant with the yellow allele.

Answer 1

@caseysorensen

Answer 2

@simplymarie_x

Answer 3

@Qwertty123

Answer 4

Call the allele for blue flowers B and the one for yellow flowers Y.

A true-breeding specimen must be homozygous, so the blue flowers must have the genotype BB and the yellow ones must be YY. (If a flower were BY, it could pass either color to its offspring, so some of the offspring wouldn't be the same color, so it wouldn't be true-breeding.)

Now when you cross a flower with genotype BB with one with genotype YY, all the offspring will be BY.

If a BY flower appears blue, then the blue allele must be dominant.

Therefore C is the correct answer.
Amy F
https://answers.yahoo.com/question/index?qid=20061222151615AAvOTCI