Concept explainers
In a type of parakeet known as a “budgie,” feather color is controlled by two genes. A yellow pigment is synthesized under the control of a dominant allele Y. Budgies that are homozygous for the recessive y allele do not synthesize yellow pigment. At an independently assorting gene, the dominant allele B directs synthesis of a blue pigment. Recessive homozygotes with the bb genotype do not produce blue pigment. Budgies that produce both yellow and blue pigments have green feathers; those that produce only yellow pigment or only blue pigment have yellow or blue feathers, respectively; and budgies that produce neither pigment are white (albino).
a. List the genotypes for green, yellow, blue, and albino budgies.
b. A cross is made between a pure-breeding green budgie and a pure-breeding albino budgie. What are the genotypes of the parent birds?
c. What are the genotype(s) and phenotype(s) of the
d. If
e. The cross of a green budgie and a yellow budgie produces offspring that are
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