In mice, black coat color is dominant to white coat colo...

Question

In mice, black coat color is dominant to white coat color. In the pedigree shown here, mice with a black coat are represented by darkened symbols, and those with white coats are shown as open symbols. Using allele symbols B and b, determine the genotypes for each mouse.

Accepted Answer

Hi, everyone. Welcome back. Here's our next problem. If unaffected parents have affected offspring for a certain autism a condition, it may imply that we have choices. A the trade is dominant, be the parents are home adidas. See the trade is recessive. D the parents are true breeds. Well, let's first get out of the way. One condition. Here, we know that it's an auto zonal condition. So it's not sex linked but carried on the autism's. We have unaffected parents. They do not express the genetic condition and affected offspring. Well, the most common way that would happen is that the parents have an alibi for that condition and have passed the alley along to their offspring. If the parents each have one ally And the Osprey inherits two. If we have a recessive condition, you'd see the situation where the parents would not be affected because of the conditions. Recessive, they're unaffected chromosome will mask the expression of that condition. But if you have to carry your parents each hetero sickness for the affected a little, their offspring can inherit those two affected alleles and then effect express the condition show have the condition where their parents don't. So the what we would expect is a recessive condition. It is important to note note that our question says it may imply. So it doesn't mean that it must be a recess condition. The other condition where you'd see unaffected parents and affected offspring for an autism. A condition is if it were a spontaneous mutation in the offspring. So that's why are quite problem says may imply rather than it must mean. But let's look through our answer choices here. Choice A says the trade is dominant. If the trade is dominant, you would not see unaffected parents passing on to affected offspring. So that's what we wouldn't, we wouldn't expect that to be our answer. Choice. B, the parents are home as I guess uh if the parents were home, as I guess we'd expect them to have the condition. So choice B is not our correct answer. I see the trait is recessive and yes, as we said, that would be a common pattern to see in the case of recessive traits, unaffected parents who are carriers for the gene and each parent passing one of those affected aliens to the offspring who then expressed the recessive condition. Choice. D says the parents are true breeds in genetics. That means essentially you expect them to be homos, I guess because a true breeding line would mean you have many, many generations that always express the same phenotype. So you presume that their hetero, I guess I mean, Hamas, I guess, excuse me, since you haven't seen any other traits pop up over generations, so that would not be our correct answer. So we can eliminate choice. D so again, if unaffected parents have affected offspring for a certain autism, a condition, it may imply that choice. See the trait is recessive. See you in the next video.

Struggling with Genetics?

In mice, black coat color is dominant to white coat color. In the pedigree shown here, mice with a black coat are represented by darkened symbols, and those with white coats are shown as open symbols. Using allele symbols B and b, determine the genotypes for each mouse.

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