The mutation which causes curly hair in dogs, such as the labradoodle seen in Figure 23, is in exon 2 of the gene and is predicted to substantially disrupt the structure of the keratin 71 protein Cadieu, This change in protein shape prevents the keratin proteins from interacting together correctly within the hair, altering the structure of the hair and resulting in a curly coat Runkel, When a dog has two curly alleles K C K C , it has a very curly coat, such as on the poodle in Figure Antigens determine blood type and can either be proteins or complexes of sugar molecules polysaccharides.
The genes in the blood group antigen family provide instructions for making antigen proteins. Blood group antigen proteins serve a variety of functions within the cell membrane of red blood cells. These protein functions include transporting other proteins and molecules into and out of the cell, maintaining cell structure, attaching to other cells and molecules, and participating in chemical reactions. There are 29 recognized blood groups, most involving only one gene. Variations polymorphisms within the genes that determine blood group give rise to the different antigens for a particular blood group protein.
The changes that occur in the genes that determine blood group typically affect only blood type and are not associated with adverse health conditions, although exceptions do occur. The A and B alleles are codominant, which is similar to incomplete dominance in that heterozygotes have an intermediate phenotype.
If both the A and B alleles are present, both will be seen in the phenotype. The O allele is recessive to both A and B. Coat variation in the domestic dog is governed by variants in three genes. Morphologic and molecular characterization of two novel Krt71 Krtg mutations: Krt71rco12 and Krt71rco Mamm Genome. OpenStax, Biology.
OpenStax CNX. Figure These pink flowers of a heterozygote snapdragon result from incomplete dominance. Figure The results of crossing two pink snapdragons. In these cases, the phenotype of each individual plant is its flower color, red, white, or pink. The question states that the inheritance of flower color in snapdragons shows incomplete dominance. Allele show in complete dominance when an intermediate phenotype is created in an organism that is heterozygous for a particular trait, which means that they have one of each allele.
In this example, the intermediate phenotype is the pink flower color, as it is a blend between the white and red flowers and has a heterozygous genotype. Punnett squares like this one are used to visually represent how alleles are inherited and predict the genotypes and phenotypes of the offspring produced by crossing parents with known genotypes. We know that pink snapdragons have the genotype CR CW.
Now we need to fill in the blank cells with the potential offspring genotypes that are able to be produced from a cross between these two pink parents. We do this by taking the alleles in the gametes from each row and column head, for example, the CR allele from this parent and the CR allele from this other parent. We can see in the Punnett square that one out of four of the offspring has the genotype CR CR and so has a red-flowered phenotype. We can also see that one out of four of the offspring has the genotype CW CW and so a white-flowered phenotype.
Finally, two out of the four offspring produced in this cross have the heterozygous genotype CR CW and so have a pink-flowered phenotype. The question asks us to determine the probability in percent that the offspring produced by this cross will have pink flowers. Therefore, the probability that the offspring produced by two pink snapdragons will also be pink is 50 percent.
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