In fruit flies, the red allele is dominant to the allele for sepia eyes. In a certain population of 1000 fruit flies, 640 flies have red eyes while the remainder have sepia eyes. How many individuals would you expect to be homozygous dominant for red eye color?

In rabbits, an allelic series helps to determine coat color: C (full color), cch (chinchilla, gray color), ch (Himalayan, white with black extremities), and c (albino, all-white). The C allele is dominant over all others, cch is dominant over ch and c, ch is dominant over c, and c is recessive to all the other alleles. This dominance hierarchy can be summarized as C > cch > ch > c. The rabbits in the following list are crossed and produce the progeny shown. Give the genotypes of the parents for following cross: Phenotypes of parents       Phenotypes of offspring Q. full color × full color      34 full color, 14 albino

Suppose a species of tulip has three alleles for the gene that codes for flower color. The CR allele produces red tulips, the Cp allele produces purple tulips, and the Cw allele produces white tulips. CR is dominant over Cp and Cw, and Cp is dominant over Cw. What is the expected phenotypic ratio in the offspring of the following crosses, in the order red: purple : white? Enter your answers as the most simplified ratio (e.g. 1: 2: 1 instead of 2 : 4:2). Enter 0 if none of the offspring from a cross will be a particular color. CRCP X CpCw- red: purple : white CRCR X CpCw- red: purple: white CpCW x CRCW - purple : CpCw x CpCw purple : - red: red : white white

In humans, there is a gene that influences the ability to smell the thioesters present in urine after asparagus is eaten. The ability to smell these compounds is an autosomal dominant trait. A is dominant and confers the ability to smell these thioesters a is recessive and does NOT confer the ability to smell these thioesters p = freq (A) = frequency of allele A in the population = number of A alleles/ total number of alleles %3D q = freq (a) = frequency of allele a in the population where p + q = 1 and, therefore, p? + 2pq + q? = 1 and %3D %D p? = freq (AA) = frequency of genotype AA = number of AA individuals/ total number of individuals %3D 2pq = freq (Aa) = frequency of genotype Aa q? = freq (aa) = frequency of genotype aa Phenotype Number of People Able to smell thioesters 378 Unable to smell thioesters 1323 Total 1701 1. Calculate p and q for this population. 2. Calculate p?, 2pq, and q? for this population.

In griffins, coat colour is determined by a single gene with a completely dominant black (B) allele and a recessive white allele (b). Beak shape is determined by a single gene with a completely dominant sharp beak allele (R) and a recessive round beak allele (r). The colour and beak genes are linked by 25 cM(= centimorgans = map units). If a female heterozygous at both loci has the dominant alleles linked in cis, she will produce gametes that have what genotypes in what ratios? Explain your answer.

In mice, the presence of a dominant A allele results in the agouti pattern of fur color, whereas the aa homozygous recessive results in a solid color pattern. The presence of another dominant B allele results in black fur color, whereas the homozygous recessive bb results in brown fur color. The presence of a third dominant C allele is required for any color to be observed (brown or black), whereas the homozygous recessive cc results in lack of any color whatsoever (albino).  What is the phenotype of a mouse with the following genotype? Aa bb cc   albino Agouti color pattern and brown Solid color pattern and brown Agouti color pattern and black Solid color pattern and black

If the frequency of the "green" form of red-green color blindness (due to an X-linked locus) is 5 percent among males, what fraction of females would be affected? Assuming H-W equilibrium what fraction of females would be heterozygous?

Butterflies show 3 phenotypes due to incomplete dominance at the D locus with alleles DY and DB giving green phenotype in heterozygotes and yellow and blue in homozygotes. A population of butterflies showed 49% yellow, and 51% blue and green. What percentage of the gametes for the next generation would contain the DB  allele?

Within a mouse population, the black fur allele (B) is dominant to the white fur allele (b) and the short whisker allele (S) is dominant to the long-whisker allele (s). A heterozygous black-furred short-whiskered mouse is crossed with a homozygous white-furred long-whiskered mouse. What percentage of the offspring will be black-furred with long whiskers?

In frost moths, two alleles of one gene determine the character difference of spotted versus striped wings and two alleles of a separate, independent gene determine the character difference of orange wing background versus white wing background. The results for four matings of moth phenotypes are shown below.     Number of progeny Mating Parental Phenotypes Spotted/orange Spotted/white Striped /orange Striped  /white 1 spotted/orange x striped/orange 623 0 637 0 2 spotted/white x striped/orange 0 0 0 712 3 spotted/white x striped/orange 122 131 128 133 4 spotted/orange x striped/white 0 0 430 422 striped= S(dominant) spotted=s (recessive) white= W(dominant) orange=w (recessive)   What are the genotypes of each parent in each cross?  If more than one genotype is possible, list the alternative possibilities.  (Remember that each mating involves a separate set of parents, so the 4 matings involve 8 separate…