The compound phenylthiocarbamide (PTC) tastes very bitter to most persons. The inability to taste PTC is controlled by a single recessive gene. In the American white population, about 70% can taste PTC while 30% cannot (are non-tasters). Estimate the frequencies of the Taster (T) and nontaster (t) alleles in this population as well as the frequencies of the genotypes.

Some individuals in a canine population is susceptible to disease X, which strikes the adults. The susceptibility is later found to be determined by a single locus, with the R allele dominant over the r allele, such that the rr individuals are susceptible to the disease and the others immune. A population genetic survey showed that 1% of the newborns carry the rr genotype. Also, an independent estimation showed that mutation rate converting R to r is 5 × 10-3 per generation. You suspected that the r allele frequency is maintained by mutation- selection balance (MSB). If your hypothesis of MSB is true, then what is the survival rate for the rr adults? (Note: the equilibrium allele frequency ĝ is calculated as ĝ where %3D u is the mutation rate and s is the selection coefficient.) 5% 50% 95% 99% None of the above

Imagine you have a VERY large garden consisting of thousands of red-flowered individuals (recessive homozygotes rr) and just a few dozen white-flowered plants (genotypes either RR or Rr) of the same species. The garden is isolated from all other flower populations. What do you think will happen to the frequency of the white-flowered plants in your garden from year to year, assuming that the two phenotypes survive and reproduce equally well, that flower color is inherited as a dominant trait, and that pollinating insects make no distinction in flower color? Why?

Phenylthiocarbamide (PTC) is an organic compound that either tastes extremely bitter or is tasteless, depending on the genotype of the taster. The tasting allele (T) is dominant over the non-tasting allele (t).  Normal skin pigmentation (N) is dominant over albinism (n).  (It is important to note that this example of PTC tasting cannot be explained with simple genetics, but for the purpose of this question, assume that it can.)  A normally-pigmented woman who cannot taste PTC has an albino father.   The woman married an albino man who can taste PTC and whose mother cannot taste PTC.  For the married couple,  1.  correctly identify their genotypes,  2.  complete a digital Punnett square showing the expected offspring of the couple, and  3.  identify the genotypic and phenotypic ratios of their offspring

Tay-Sachs disease is a recessive genetic disease. Individuals with this disease rarely survive past the age of four. In the general population, approximately 1 person in 300 carries the allele for this disease. However, in some populations, including the Irish Americans, the Ashkenazi Jews, and the Cajuns from Louisiana, the proportion of Tay-Sachs carriers is much higher (1 in 27 to 1 in 50) than in other populations. Such high frequency of an otherwise rare allele is expected when    Question 24 options:   populations experienced disruptive selection   populations were founded by a small number of settlers   the allele is advantageous at the heterozygous state    populations have higher than average mutation rates   populations experienced stabilizing selection

There are two incomplete-dominant alleles for petal color in a population of flowers. 36% of the flowers have red petals, 16% of the organisms have white petals, and 48% of the flowers have pink petals. What percentage of alleles in this population code for red petals (R)? Phenotype Genotype Red RR Pink Rr White rr

There is a gene that causes people to have crumbly earwax. This gene is expressed as a complete dominant: Individuals who are homozygous dominants (CC) or heterozygous (Cc) have crumbly earwax. Homozygous recessives (cc) have gooey earwax. There are 100 people, 64 of whom have crumbly earwax. Assuming Hardy-Weinberg conditions, what is the frequency of the c allele on Paradise Island? Group of answer choices 0.80 This cannot be answered without more information. 0.60 0.36 None of the above.

The ability to roll your tongue is a dominant genetic trait passed on from generation to generation. Tongue rolling is the ability to roll the lateral edges of your tongue upward into a tube. The frequency of the tongue rolling trait was collected from 1,000 individuals each year 1925 to 2000 and is show in the data table below. Year Tongue Rolling Inability to Roll Tongue 1925 67% 33% 1950 68% 32% 1975 63% 37% 2000 67% 33%   (a)   Determine if the human population was in equilibrium from 1925 to 2000. Justify your response. (b)   (b)  Discuss how the Hardy Weinberg Principle can be used to determine whether this population is evolving (c)   (c)  Identify and describe THREE factors that would affect whether the population of Tongue Rollers is in Hardy Weinberg equilibrium. (d)   (d)  A scientist recently stated a claim that it is unlikely that the inability to roll your tongue will disappear from the population. Provide reasoning to explain…

In a  certain  breeding population , it is  known for  certain that  only 7.8% of  the individuals  are "true breeding" for the  dominant phenotype.  What would be  the predicted  frequency of  individuals that are "true-breeding" for the recessive phenotype?

In some populations of grasses, the ability to grow in soil sprayed with a certain herbicide is a dominant trait determined by the allele "R". In a population at genetic equilibrium, 91% of the seeds can germinate in sprayed soil. What are the frequencies of "R" and "r"? What percentage of the plant that germinates in the soil will be heterozygotes?