In the rats identified in Problem 10, a third independen...

Question

In the rats identified in Problem 10, a third independently assorting gene involved in determination of coat color is the C gene. At this locus, the genotype C– permits expression of pigment from genes B and D. The cc genotype, however, prevents expression of coat color and results in albino rats. For each of the following crosses, determine the expected phenotype ratio of progeny.

BBDdcc×BbddCc

Accepted Answer

Hi, everyone. Let's look at our next question. In cats. A dominant allele F causes fur to be short and its recessive allele F produces long fur eye color is controlled by an independently assorting gene. The dominant allele G produces green eyes and the recessive allele G produces blue eyes. When cats from a true breeding, short, green eyed variety are crossed with cats from a true breeding long blueeyed variety. What would be the genotype of their progeny? Choice? A homozygous dominant for both F and G choice B, homozygous dominant F, heterozygous G choice C heterozygous for both F and G or choice D homozygous recessive for both F and G. So let's think about what our cross is here. When we talk about a true breeding line, we assume that the individuals are homozygous. So the one parent is from a true breeding, short green eyed variety. So we know the short fur is the dominant allele for F. So we have homozygous dominant for F and then green eyes are also dominant. So we have homozygous dominant for all L G and that is crossed with the other parent from a true breeding long blueeyed variety. So that would be homozygous, recessive for gene F and homozygous recessive for gene G. So we've got homozygous dominant, crossed with homozygous recessive. What is the genotype of the progeny? Well, that's nice and straightforward. The progeny will all be heterozygous. One parent can only dominate, only donate a dominant, all the other parent can only give a recessive allele. So the progeny will be heterozygous for both jeans. And when we look at our answer choices, we see that that is choice. C So again, with the two true breeding lines or both dominant traits and both recessive traits. The genotype of the progeny is choice. C heterozygous for gene F and heterozygous for gene G. See you in the next video.

Key Concepts

Independent Assortment

Genotype and Phenotype

Epistasis

Watch next