Genetic Analysis: An Integrated Approach (3rd Edition)
3rd Edition
ISBN: 9780134605173
Author: Mark F. Sanders, John L. Bowman
Publisher: PEARSON
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Textbook Question
Chapter 20, Problem 7P
Over the course of many generations in a small population, what effect does random genetic drift have on allele frequencies?
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
Let’s assume that the marbles are species of praying mantises and that the new environment consists of greenery and many bright red and white flowers
a) Which colors in the genetic drift population would have better fitness in this new environment? Why/how?
b) Which of the colors would have less fitness? Why/how?
c) What would you expect to happen to the allele frequency for the following forms of the gene:
-Green
-Yellow
-Red
-Blue
-Orange
How does population size affect the likelihood of changes in allele frequencies by chance alone? Can significant changes in allele frequencies (that is, evolution) occur as a result of genetic drift?
What Causes Allele Frequencies to Change in Real Populations?
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...
Knowledge Booster
Learn more about
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
- How Can We Measure Allele Frequencies in Populations? Drawing on your newly acquired understanding of the HardyWeinberg equilibrium law, point out why the following statement is erroneous: Because most of the people in Sweden have blond hair and blue eyes, the genes for blond hair and blue eyes must be dominant in that population.arrow_forwardHow Can We Measure Allele Frequencies in Populations? What are four assumptions of the HardyWeinberg law?arrow_forwardA hypothetical population has two alleles for a “B" gene: B1 and B2. In a random sample of 50 diploid zygotes (for a total of 100 alleles), the following genotypes were found: 20 B1B1, 20 B1B2, and 10 B2B2 The above values represent the initial genotype frequencies of zygotes in the population. Let's say that selection acts against the B2 allele, and all 10 individuals with B2B2 genotype die off before reaching maturity (leaving 0 B2B2 individuals). (The number of surviving adults in the population is 40, so the number of alleles is 80). What is the new observed frequency of the homozygous dominant genotype? O A. 0.10 О В. О.70 O C. 0.25 O D.0.50 O E. 0.75arrow_forward
- You are studying a single-gene locus with two alleles in a population that is in Hardy–Weinberg equilibrium. Examination of a large sample of individuals from the population reveals there are six times as many heterozygotes as there are homozygote recessive individuals in this population. What is the frequency of the recessive allele? I don't know how to start his calculation with just a ratio of 6:1 I found an answer online that says the frequency of q=0.25 but the calculations (below) don't make sense to me. Please help me. What is the answer and how do I get to it? Hardy-Weinberg equation p2+2pq+q2=1 2pq/q2= 6/1 2p= 6q 2(1-p)= 6q 2-2q=6q q=0.25arrow_forwardHow does Genetic Drift and Non-random mating fit within the scope of Population Genetics?arrow_forwardWhat is the intuitive meaning of the mean fitness of a population? How does its value change in response to natural selection?arrow_forward
- Example: I go to a different population of fruit flies that have the same two alleles for eye-color. I suspect that the alleles occur in different frequencies in this second population. I sample 1000 flies and discover 10 that have brown eyes. What are the estimated frequencies of the "R" and "r" alleles in this population? Answer: Again, p2 + 2pq + q2 = 1. The term q2 = the relative frequency of homozygous recessive individuals, which corresponds to the ten brown-eyed flies I counted out of 1000 flies sampled. Thus, q2 = 10/1000 = 1/100. q = the square root of 1/100 or 0.1. Thus the frequency of "r" in this second population is 0.1 and the frequency of the "R" allele is 1 - q or 0.9. Problem 1: Phenylketonuria (PKU) is a disease caused by the build-up of the byproducts of metabolizing phenylalanine. It is caused by a defective, recessive allele. If a child is homozygous for this recessive allele, it will develop PKU. In the United States, PKU is detected in approximately 1 in 10,000…arrow_forwardIn a population, the dominant phenotype of a certain trait occurs 91% of the time. What is the frequency of the dominant allele?arrow_forwardWhich type of selection (directional, disruptive, stabilizing) changes the overall average phenotype in a population? How does it do this? What does "additive” mean? Why aren't dominant and epistatic variances considered to be additive?arrow_forward
- How does population size affect genetic drift?arrow_forwardAt least one of the discoverers of this genetic equilibrium (Hardy) developed this HW equation to show that the dominant allele will not always take over the population just because that allele has a dominant effect on the phenotype. What additional factor would have to be present to cause a dominant allele to increase to a frequency of 100%? Why is this factor essential for the dominant allele to “take over” the gene pool?arrow_forwardIn corn, kernel color is governed by a dominant allele for white color (W) and by a recessive allele for yellow (w). A random sample of 152 kernels from a population that is in Hardy- Weinberg equilibrium reveals that 35 kernels are yellow and 117 kernels are white. What is the frequency of individuals with the homozygous dominant genotype?arrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning
Human Heredity: Principles and Issues (MindTap Co...
Biology
ISBN:9781305251052
Author:Michael Cummings
Publisher:Cengage Learning
Mendelian Genetics and Punnett Squares; Author: Professor Dave Explains;https://www.youtube.com/watch?v=3f_eisNPpnc;License: Standard YouTube License, CC-BY
The Evolution of Populations: Natural Selection, Genetic Drift, and Gene Flow; Author: Professor Dave Explains;https://www.youtube.com/watch?v=SRWXEMlI0_U;License: Standard YouTube License, CC-BY