Download Incomplete dominance

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GENETICS: BEYOND THE BASICS
INCOMPLETE DOMINANCE
I remember Incomplete Dominance in the form of an example
like so:
RED Flower x WHITE Flower ---> PINK Flower
With incomplete dominance, a cross between organisms with
two different phenotypes produces offspring with a third
phenotype that is a blending of the parental traits.
EXAMPLE
R = allele for red
flowers
W = allele for white
flowers
red x white ---> pink
RR x WW ---> 100% RW
Solve these genetics problems. Be sure to complete the Punnett square to show how
you derived your solution.
1. In radishes, the gene that controls color exhibits incomplete dominance. Purebreeding red radishes crossed with pure-breeding white radishes make purple radishes.
What are the genotypic and phenotypic ratios when you cross a purple radish with a
white radish?
2. Certain breeds of cattle show incomplete dominance in coat color. When pure
breeding red cows are bred with pure breeding white cows, the offspring are roan (a
pinkish coat color). Summarize the genotypes & phenotypes of the possible offspring
when a roan cow is mated with a roan bull.
3. A cross between a blue blahblah bird & a white blahblah bird produces offspring that
are silver. The color of blahblah birds is determined by just two alleles.
a) What are the genotypes of the parent blahblah birds in the original cross?
b) What is/are the genotype(s) of the silver offspring?
c) What would be the phenotypic ratios of offspring produced by two silver blahblah
birds?