CELL DIVISION
MEIOSIS AND GENETIC VARIATION
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Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
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BBEe will be brown.
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BbEe will be brown.
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Bbee will be brown.
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BBee will be yellow.
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bbee will be brown.
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Detailed explanation-1: -In Labrador retrievers, there is a gene called black that is involved in determining coat color. This gene has two alleles: B and b. Another gene called extension is also involved in determining coat color. This gene also has two alleles: E and e.
Detailed explanation-2: -There are four known alleles at this gene in the Labrador Retriever: one is the allele for black (designated as B) and three different alleles that result in chocolate (collectively designated as b). In determining if your puppies will be black or chocolate, the black coat color (B) is dominant to the chocolate (b).
Detailed explanation-3: -The three recognized coat colours in Labrador retrievers are black, chocolate and yellow. Observable within-breed variation among coat colours is determined by two genes: MC1R (melanocortin 1 receptor) and TYRP1 (tyrosinase related protein 1).
Detailed explanation-4: -Labradors of genotype E/-will have dark-colored fur (either black or brown) while yellow labradors have the recessive genotype e/e. Since having the genotype e/e will result in a yellow coat no matter whether the dog is B/-or b/b, carrying two copies of the e allele is recessively epistatic to the B gene.