In unicorns, two autosomal loci interact to determine the type of tail. One locus controls whether a tail is present at all; the allele for a tail (T) is dominant over the allele for tailless (t). If a unicorn has a tail, then alleles at a second locus determine whether the tail is curly or straight. Farmer Baldridge has two unicorns with curly tails: when he crosses them, 12 of the progeny have curly tails, 14 have straight tails, and 14 do not have a tail. Give the genotypes of the parents and progeny in Farmer Baldridge’s cross. Explain how he obtained the 2 : 1 : 1 phenotypic ratio in his cross.

In dogs, black coat color (B) is dominant to yellow coat color (b), and straight fur (C) is dominant to curly fur (c). The coat color gene and the fur texture gene are on different chromosomes, so they assort independently, and are not sex-linked. In a cross between two BbCc parents, predict the fraction of offspring with black coat color and straight fur. Give two digits after decimals.

a) 1/3 b)1/2 c)1/8

Two fruit flies (Drosophila melanogaster) were crossed. The cross was between a homozygous red-eyed, wingless female and a white-eyed male heterozygous for wings. Recall that red eyes (R) is dominant over white eyes (r) and is inherited on the X chromosome (sex-linked) and as such, eye colour alleles should be written as superscript. In addition, the autosomal trait wings (W) is dominant over wingless (w). 1. List the female genotype 2. List the male genotype 3. Construct a Punnett Square for this dihybrid cross on a piece of paper, to determine what the offspring of such a cross would be with respect to sex, eye colour & wings. 4. Using the information from your Punnett Square answer the following: a. What genotypes did you get (list all genotype combinations; if you have more than one of the same kind, you do NOT have to re-list it.) b. What are the phenotypic ratios of the offspring with respect to sex, eye colour and wings?

What is the approximate percentage chance that individual V.2, shown in the pedigree diagram below will have inherited the X- linked recessive allele shown to be carried by his great-great-grandmother? Note: only type the number, not the percentage symbol. Answer: The chance that individual V.2 shown in the pedigree below has inherited the X-linked recessive allele shown to be carried by his great-great grandmother is approximately Blank 1 percent. 노 ㅍ먹이 12 I 마일 메인 de 먹어 요 58 ㅁ + ܡܐ

In the rat, the pattern of coat color is affected by a gene with two alleles. PH is the allele for hooded, in which the animal is mostly white with color restricted to the shoulders and neck. P+ is the normal solid body color allele. These two alleles exhibit incomplete dominance, so that heterozygotes have white bellies only. A true-breeding solid strain is crossed with a true-breeding hooded strain, to produce an F₁ generation that is all white belly. The F₁ generation rats are mated with each other to produce 800 F₂ offspring. Below is a table that gives the observed number of each phenotype in the F2 and also gives you the expected number. Question: If you perform a Chi-square goodness of fit test, what is the value of Chi square X² (Express your answer to the hundredths.) solid white belly hooded Σ Observed 195 420 185 800 Expected 200 400 200 800

A breeder is interested in a new coat colour in mice. This trait is controlled by a single autosomal gene (Gene T) with two alleles. The T-allele results in a yellow coat colour, while the recessive allele causes a cream coat colour. The breeder has a yellow mouse. Can you suggest how the breeder can determine the genotype (TT or Tt) of his mouse in a single cross? Describe this cross and provide details on how you would interpret the results.

In the red spotted butterfly there are two traits under investigation.  The wing margin can be either notched (N) or straight (n) and the wing color can be either pale yellow (b) or bright yellow (B).  A bright yellow male with straight wing margins was crossed with a bright yellow female with notched wing margins.  All of the resulting progeny had notched wings and both color patterns were present.  From these data determine the genotypes of the butterflies used in the original cross.