Genetic Analysis: An Integrated Approach (3rd Edition)
3rd Edition
ISBN: 9780134605173
Author: Mark F. Sanders, John L. Bowman
Publisher: PEARSON
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Chapter 20, Problem 24P
In the mouse, Musmusculus, survival in agricultural fields that are regularly sprayed with a herbicide is determined by the genotype for a detoxification enzyme encoded by a gene with two alleles, F and S. The relative fitness values for the genotypes are:
a. Why will this pattern of natural selection result in a stable equilibrium of frequencies of F and S?
b. Calculate the equilibrium frequencies of the alleles.
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The trait that natural selection “selects for” is lifetime Darwinian fitness. If relative matching of the moths to the background is determining fitness differences, is there any difference in other fitness components in the color morphs of Biston betularia that is influencing the direction of evolution in the three populations shown in the graph?
The trait that natural selection “selects for” is lifetime Darwinian fitness. If relative matching of the moths to the background is determining fitness differences, is there any difference in other fitness components in the color morphs of Biston betularia that is influencing the direction of evolution in the three populations shown in the graph? Give a reason for your answer.
Consider a hypothetical beetle whose back abdomen pattern is determined by two alleles A1 and A2. Beetles that are homozygous for the 'A1' allele have solid coloring, beetles that are heterozygous (A1A2) are spotted, and beetles that are homozygous for the A2 allele are striped. You find a population of 100 of these beetles and count each phenotype (shown below). TRUE or FALSE: this population is in Hardy-Weinberg equilibrium? What is the predicted frequency of spotted beetle?
Solid Beetles = 49
Spotted Beetles = 35
Striped Beetles = 16
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Chapter 20 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
Ch. 20 - 20.1 Compare and contrast the terms in each of the...Ch. 20 - In a population, what is the consequence of...Ch. 20 - 20.3 Identify and describe the evolutionary forces...Ch. 20 - Describe how natural selection can produce...Ch. 20 - Thinking creatively about evolutionary mechanisms,...Ch. 20 - 20.6 Genetic drift, an evolutionary process...Ch. 20 - Over the course of many generations in a small...Ch. 20 - Catastrophic events such as loss of habitat,...Ch. 20 - 20.9 George Udny Yule was wrong in suggesting that...Ch. 20 - 20.10 The ability to taste the bitter compound...
Ch. 20 - Figure 20.6 illustrates the effect of an ethanol ...Ch. 20 - 20.12 Biologists have proposed that the use of...Ch. 20 - 20.13 Two populations of deer, one of them large...Ch. 20 - 20.14 Directional selection presents an apparent...Ch. 20 - 20.15 What is inbreeding depression? Why is...Ch. 20 - 20.16 Certain animal species, such as the...Ch. 20 - Genetic Analysis 20.1 predicts the number of...Ch. 20 - 20.18 In a population of rabbits, and . The...Ch. 20 - Sickle cell disease (SCD) is found in numerous...Ch. 20 - 20.20 Epidemiologic data on the population in the...Ch. 20 - The frequency of tasters and nontasters of PTC...Ch. 20 - Tay-Sachs disease is an autosomal recessive...Ch. 20 - 20.23 Cystic fibrosis (CF) is the most common...Ch. 20 - 20.24 In the mouse, Mus musculus, survival in...Ch. 20 - 20.25 In a population of flowers growing in a...Ch. 20 - Assume that the flower population described in the...Ch. 20 - 20.27 ABO blood type is examined in a Taiwanese...Ch. 20 - 20.28 A total ofmembers of a Central American...Ch. 20 - 20.29 A sample offield mice contains individuals...Ch. 20 - Prob. 30PCh. 20 - Albinism, an autosomal recessive trait...Ch. 20 - 20.32 The frequency of an autosomal recessive...Ch. 20 - 20.33 Evaluate the following pedigree, and answer...Ch. 20 - Evaluate the following pedigree, and answer the...Ch. 20 - The following is a partial pedigree of the British...Ch. 20 - Draw a separate hypothetical pedigree identifying...Ch. 20 - Prob. 37PCh. 20 - 20.38 Achromatopsia is a rare autosomal recessive...Ch. 20 - 20.39 New allopolyploid plant species can arise by...
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Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, biology and related others by exploring similar questions and additional content below.Similar questions
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- When we take, say, 100 individuals of a species of beetle from the wild and place them in a new environment that is not so different that they are unable to thrive but different enough so that they are experiencing a new selective regime, say, a lower temperature, what typically happens? A - Sexual selection causes some larvae to be able to survive in the cooler temperatures and other individuals to be unable to survive because they need warmer temperatures. B - We are unable to measure phenotypic selection, presumably because we do not have much variation among individuals for how they handle temperature. C - The founder event assures us that the new population will be strictly representative of the source population (especially if we took all the 100 from the same location rather that from throughout the range of the species). D - The population evolves to be tolerant of the lower temperature; it can do this because of latent variation already in the 100 founding individuals. E -…arrow_forwardif a population of jumping spiders consists of 40 females and 40 males, what is the effective population size? Give the appropriate equation and show your work. Will genetic drift be an important evolutionary force in this population? Why or why not? If your answer is "yes", what does genetic drift do to allele frequencies? If your answer is "no", name two forces other than genetic drift that might be important in determining allele frequencies. asaparrow_forwardSuppose a population has two alleles at a particular locus, and individuals with different diploid genotypes at this locus have different probabilities of survival and expected offspring, as given in the table below: Genotype % Surviving to adulthood Expected offspring GG 90% 11 Gg 80% 15 gg 50% 28 Calculate the absolute fitness, W, for each genotype, and then the relative fitness, w, using the smallest absolute fitness value as your reference. Assume that the selection differential s is equal to the difference in relative finesses of the heterozygote, Gg, genotype, and the least-fit genotype. If there are 311 individuals who are homozygous for the G allele in a population of 4,659, and we ignore the effect of genetic drift, how much should the frequency of the G allele change over one generation of natural selection? (Give your answer up to four decimal places).arrow_forward
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