Biology
12th Edition
ISBN: 9781260494570
Author: Raven, Peter
Publisher: MCGRAW-HILL HIGHER EDUCATION
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 20, Problem 1U
Assortative mating
a. affects genotype frequencies expected under Hardy–Weinberg equilibrium.
b. affects allele frequencies expected under Hardy–Weinberg equilibrium.
c. has no effect on the genotypic frequencies expected under Hardy–Weinberg equilibrium because it does not affect the relative proportion of alleles in a population.
d. increases the frequency of heterozygous individuals above Hardy–Weinberg expectations.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Which of the following statements is true about linkage disequilibrium?
a.
New alleles are born into a population in LE with the surrounding loci
b.
Genetic hitchhiking results from LD between surrounding loci and a locus under strong selection
c.
Loci in LE in two different populations with different allele frequencies will remain in LE when the two populations completely merge into a single population.
d.
The greater the selection on a locus, the smaller the haplotype block maintained around it
e.
D= 0.15 indicates that two loci are in greater LD than D= -0.23
Consider a gene with two alleles, L and M, that exhibit complete dominance. The
table below provides the relative fitnesses of the three genotypes in two
populations.
LL
LM
MM
Population 1
0.8
0.3
0.3
Population 2
0.9
1.0
1.0
a. Which allele is dominant, and how do you know?
b. Which allele will increase (in each population), and how do you know?
c. In which population will the change in allele frequencies occur more
quickly, and how do you know?
A population has 25 individuals of genotype AA, 25 individuals of genotype aa, and 50 individuals of genotype Aa. Is this population in Hardy Weinberg equilibrium? Why or why not?
Group of answer choices
A. No because p2 + 2pq + q2 does not equal 1
B. Yes because p2 + 2pq + q2 = 1
C. Yes because the genotype frequencies match HW expectations based on allele frequencies
D. No because there are more heterozygotes than expected under Hardy Weinberg
E. No because there are fewer heterozygotes than expected under Hardy Weinberg
Chapter 20 Solutions
Biology
Ch. 20.1 - Define evolution and population genetics.Ch. 20.1 - Prob. 2LOCh. 20.2 - Explain the HardyWeinberg principle.Ch. 20.2 - Describe the characteristics of a population that...Ch. 20.2 - Prob. 3LOCh. 20.3 - Define the five processes that can cause...Ch. 20.3 - Prob. 2LOCh. 20.4 - Prob. 1LOCh. 20.4 - Prob. 2LOCh. 20.4 - Demonstrate how the success of different...
Ch. 20.5 - Prob. 1LOCh. 20.5 - Prob. 2LOCh. 20.5 - Prob. 3LOCh. 20.6 - Define frequency-dependent selection, oscillating...Ch. 20.6 - Prob. 2LOCh. 20.7 - Define and contrast disruptive, directional, and...Ch. 20.7 - Prob. 2LOCh. 20.8 - Explain how experiments can be used to test...Ch. 20.9 - Prob. 1LOCh. 20.9 - Prob. 2LOCh. 20.10 - Prob. 2LOCh. 20 - If all white cats died, what proportion of the...Ch. 20 - Assuming that the values on the x-axis represent...Ch. 20 - Prob. 3DACh. 20 - Prob. 4DACh. 20 - Examine the index of copper tolerance on nonmine...Ch. 20 - Prob. 6DACh. 20 - Why are rare alleles particularly likely to be...Ch. 20 - Prob. 2IQCh. 20 - Prob. 3IQCh. 20 - Prob. 4IQCh. 20 - Prob. 5IQCh. 20 - Prob. 6IQCh. 20 - Prob. 7IQCh. 20 - Prob. 8IQCh. 20 - Prob. 9IQCh. 20 - Assortative mating a. affects genotype frequencies...Ch. 20 - When the environment changes from year to year and...Ch. 20 - Many factors can limit the ability of natural...Ch. 20 - Stabilizing selection differs from directional...Ch. 20 - Founder effects and bottlenecks are a. expected...Ch. 20 - Relative fitness a. refers to the survival rate of...Ch. 20 - For natural selection to result in evolutionary...Ch. 20 - Prob. 8UCh. 20 - In a population of red (dominant allele) or white...Ch. 20 - Genetic drift and natural selection can both lead...Ch. 20 - Prob. 3ACh. 20 - Prob. 4ACh. 20 - In Trinidadian guppies a combination of elegant...Ch. 20 - On large, black lava flows in the deserts of the...Ch. 20 - Based on a consideration of how strong artificial...
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? In a population where the females have the allelic frequencies A = 0.35 and a = 0.65 and the frequencies for males are A = 0.1 and a = 0.9, how many generations will it take to reach HardyWeinberg equilibrium for both the allelic and the genotypic frequencies? Assume random mating and show the allelic and genotypic frequencies for each generation.arrow_forwardIn a population at Hardy-Weinberg equilibrium, 190 out of 1000 individuals have polydactyly. Note that the trait is dominant. a. What is the frequency of the dominant and recessive alleles? b. How many are expected to be heterozygotes for the trait? c. How many are expected to be homozygous dominant?arrow_forwardI. A population called the founder generation, consisting of 2000 AA individuals, 2000 Aa individuals, and6000 aa individuals is established on a remote island.Mating within this population occurs at random, thethree genotypes are selectively neutral, and mutationsoccur at a negligible rate.a. What are the frequencies of alleles A and a in thefounder generation?b. Is the founder generation at Hardy-Weinbergequilibrium?c. What is the frequency of the A allele in the secondgeneration (that is, the generation subsequent to thefounder generation)?d. What are the frequencies for the AA, Aa, and aagenotypes in the second generation?e. Is the second generation at Hardy-Weinbergequilibrium?f. What are the frequencies for the AA, Aa, and aagenotypes in the third generation?arrow_forward
- A. The Hardy-Weinberg Equilibrium is important because it serves as a null hypothesis in studies that evaluate evolution of species. it explains how evolution works. it predicts how allele and genotype frequencies will change over time. it clarifies how traits are passed from parent to offspring. B. Hardy-Weinberg Equilibrium occurs frequently in natural populations. predicts changes in allele and genotype frequencies. is inhibited by random mating. assumes large population sizes.arrow_forwardConsider a gene with two alleles, C and M. The table below describes fitness for different genotypes in two populations. Fitness CC CM MM Population 1 1.0 1.0 0.6 Population 2 0.9 0.9 1.0 Which of the following is true based on this table? A.) C is recessive and M is dominant B.) M is recessive and C is dominant C.) Neither allele is dominant D.) C is dominant in population 1 and M is dominant in population 2arrow_forwardA. Population 1 is in Hardy-Weinberg equilibrium; the frequency of allele A is 0.5. B. Two of the populations are not in Hardy-Weinberg equilibrium.arrow_forward
- Assuming a population is in Hardy-Weinberg equilibrium, an increase in the frequency of the p(A) allele from 0.6 to 0.9 would result in which of the following outcomes? a. A decrease in the number of homozygous dominant individuals within the population b. A decrease in the number of homozygous recessive individuals within the population c. An increase in the number of homozygous recessive individuals within the population d. An increase in the number of heterozygotes within the population e. No change in genotypic frequency within the populationarrow_forwardTheHardy-Weinberg principle states that:a.genotypic changes will result in phenotypic changes.b.phenotypic changes will result in genotypic changes.c.allelic frequencies within a population will not change unless certainconditions are met.d.allelic frequencies within a population will change unless certainconditions are met.e.none of the choices apply.arrow_forwardWhat is the expected frequency of heterozygotes in a population with allelic frequencies xand y that is in Hardy–Weinberg equilibrium?a. x + yb. xyc. 2 xyd.( x − y)2arrow_forward
- A gene has two alleles A (frequency = p) and a(frequency = q). If a population is at Hardy-Weinbergequilibrium, develop mathematical expressions interms of p and q that predict the following matingfrequencies:a. Between two AA homozygotesb. Between two aa homozygotesc. Between two Aa heterozygotesd. Between an AA homozygote and an aa homozygotee. Between an AA homozyote and an Aa heterozygotef. Between an aa homozygote and an Aa heterozygote Considering your answers to parts (a)–(f):g. Do the six possibilities listed account for all possible matings? How would you know whether this istrue mathematically? Demonstrate this latter pointby setting p equal to an arbitrary number between0 and 1 such as 0.2.h. Can you develop a simple, general rule for calculating the mating frequencies between individualsof the same genotype versus the mating frequencies between individuals of different genotypes?i. If the population is equally divided between malesand females, what proportion of all matings…arrow_forwardA new species of snail was discovered. Your initial population genetics survey found that fA:0.48. To determine the primary mode of reproduction you survey the population again in one generation. You collect 100 individuals in the next generation. The composition of your collection is AA=38, Aa=20, aa=42. What is the primary mode of reproduction? a. random mating b. not enough information to determine c. nonrandom mating due to inbreedingarrow_forwardmagine a population in which the survival of A1A1 homozygotes is 80 percent as great as that of A1A2 heterozygotes, while the survival of A2A2 homozygotes is 95 percent that of the heterozygotes. a. What is p, the frequency of the A2 allele, at polymorphic equilibrium? Show your work for all calculations. c. Now suppose the population has reached this equilibrium, but that the environment then changes so that the relative fitnesses of A1A1, A1A2, and A2A2 become 1.0, 0.95, and 0.90. What will p be in the adults after one generation of selection in the new environment?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