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GENETICS!! NEED HELP!: The color pattern is species of duck is determined by a single pair of genes with three alleles. The D(H) and D(R) alleles are codominant, while d allele is recessive to both. How many phenotypes are possible in a group of ducks that contain all of the possible combinations of alleles?

User Dan Benamy
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2 Answers

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Final answer:

There are three alleles for duck color patterns with D(H) and D(R) being codominant and d being recessive. Considering the genetic interactions, five different phenotypes are possible with a blend of traits appearing in the D(H)D(R) codominant combination.

Step-by-step explanation:

In a species of ducks with a single pair of genes determining color pattern, three alleles exist: D(H), D(R), and d. The D(H) and D(R) alleles are codominant, meaning that if a duck inherits one of each of these two alleles, the resulting phenotype will be a mixture or blending of both traits. The d allele is recessive, so it will only be expressed in the phenotype when the individual is homozygous recessive, meaning it has two copies of the d allele.

Considering these genetic interactions, we can determine the number of phenotypes possible. When we have codominance and a recessive allele, we can expect multiple phenotypes. Specifically, the potential combinations of alleles are D(H)D(H), D(H)D(R), D(H)d, D(R)D(R), D(R)d, and dd. Each pair results in a distinct phenotype, except for the D(H)D(R) combination, which will have a unique blend of the D(H) and D(R) characteristics due to codominance. Hence, a total of five different phenotypes are possible in this group of ducks.

User Kishore Barik
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In an inheritance pattern of codominance, we can see many phenotypes. We should begin by listing all the possible genotypes and associated genotypes:
Genotypes Phenotypes
D(H) D(H) H
D(H) D(R) HR
D(H) d H
D(R) D(R) R
D(R) d R
d d d

If we look at the phenotypes, there are two ways to get the "H" phenotype, two ways to make the "R" phenotype, one way to make the "HR" phenotype. and one way to make the "d" phenotype. That means there are four separate phenotypes possible.
User Lomanf
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