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Codominance. Codominance - a condition in which two dominant alleles are expressed at the same time. Neither allele is dominant or recessive. The alleles do not blend in the phenotype.
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Codominance • Codominance- a condition in which two dominant alleles are expressed at the same time. • Neither allele is dominant or recessive. • The alleles do not blend in the phenotype. • Example: Homozygous red cows crossed with homozygous white cows will generate cows with a roan coat. Roan coats consist of a mixture of all red hairs and all white hairs. • Each hair is either all red or all white therefore it is codominant!
How to Show Codominance… • Capital letters with superscripts are often used to represent genotypes in codominance. • Genotype for homozygous red coat: • Genotype for homozygous white coat: • Genotype for heterozygous animal with roan coat:
The alleles for hair texture in Koala bears will produce straight hair if homozygous for the trait. Curly hair if homozygous for the trait or straight & curly if heterozygous for the trait. Cross a straight haired koala with a curly haired Koala. What are the genotypic and phenotypic ratios of their offspring?
Two lop-eared rabbits are bred. One of the rabbits is black and the other has both black & grey fur. What would be the genotypic ratios and phenotypic ratios of their offspring?
Alec has a white mouse & a black mouse. Black coloration is dominant to white. Over a period of 2 years their offspring number 90 babies. If 48 of the babies were white, what are the genotypes of the parents.
In Koalas brown fur is dominant over grey fur. If the pair in the San Diego Zoo produced 25 offspring in their lifetime and 19 were brown 6 were grey. What did the zookeepers determine as the genotype of the parents?