<LCPO> BIOLOGY
12th Edition
ISBN: 9781266216398
Author: Raven
Publisher: MCG CUSTOM
expand_more
expand_more
format_list_bulleted
Concept explainers
Textbook Question
Chapter 20, Problem 4U
Stabilizing selection differs from directional selection because
a. in the former, phenotypic variation is reduced but the average phenotype stays the same, whereas in the latter both the variation and the mean phenotype change.
b. the former requires
c. intermediate
d. None of the choices is correct.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solutionStudents have asked these similar questions
Stabilizing selection on a trait tends toa. make the trait more extreme.b. reduce variability in the trait.c. decrease the frequency of alleles associated with the trait.d. result in elaborate male ornaments.
A gene exists in two alleles, and the heterozygote has the highest fitness. This situation is likely to result in
a. directional selection. c. disruptive selection.
b. stabilizing selection. d. balancing selection.
You are examining the gene in your snail population that confers resistance to a parasite. There are multiple alleles at this locus. Identify the characteristics that would result in the greatest increase in allele frequency (not necessarily the greatest allele frequency) in one single generation of the resistant allele.
Answer
Resistant allele acts…
Initial resistant allele frequency…
Selection strength is…
a.
dominantly
high
weak
b.
recessively
low
strong
c.
dominantly
low
strong
d.
recessively
high
weak
a.
Answer a.
b.
Answer b.
c.
Answer c.
d.
Answer d.
Chapter 20 Solutions
<LCPO> 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
- Which of the following is the MOST important characteristic of a trait for it to undergo descent with modification? A. It must be heritable. B. It must exhibit variation. C. It must exhibit phenotypic plasticity. D. Variation in the trait must be accompanied by variation in fitness.arrow_forwardYou are examining the gene in your snail population that confers resistance to a parasite. There are multiple alleles at this locus. Identify the characteristics that would result in the greatest increase resistant allele. allele frequency (not necessarily the greatest allele frequency) in one single generation of the Answer Resistant allele acts.. Initial resistant allele frequency... Selection strength is... dominantly high weak la. b. recessively low strong dominantly low strong С. d. recessively high weak O a. Answer a. O b. Answer b. O c. Answer C. O d. Answer d.arrow_forwardYou are studying a genetically modified mouse that produces electric blue fur, which is not a fur color observed in nature. You notice that females prefer males that have the blue fur when given a choice test for mates. This result supports which of the following models of sexual selection? a. Sexual selection for indirect benefits b. Sexual selection for direct benefits c. Sexual selection for arbitrary traits d. None of the abovearrow_forward
- Selection that causes one extreme phenotype to be more frequent in a population is an example ofa. disruptive selection.b. stabilizing selection.c. directional selection.d. equivalent selection.arrow_forwardThe good genes hypothesis is a theory that explains what? a. why more fit individuals are more likely to have more offspring b. why alleles that confer beneficial traits or behaviors are selected for by natural selection c. why some deleterious mutations are maintained in the population d. why individuals of one sex develop impressive ornamental traitsarrow_forwardA population occupies heterogeneous environments in which the fitness of some genotypes is higher in one environment and the fitness of other individuals is higher in another environment. This situation is likely to result in a. directional selection. b. stabilizing selection. c. disruptive selection. d. balancing selection.arrow_forward
- Consider 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_forwardWhat is the difference between artificial selection (e.g., greyhounds that are bred for speed) and natural selection? a. In artificial selection, the genetic variation introduced into the population is limited, but in natural selection, it is not b. In artificial selection, the environment is the selective force, while in natural selection, humans are the selective force c. In natural selection, the environment is the selective force, while in artificial selection, humans are the selective force d. Unlike other species, dogs are not subject to natural selection e. Both A & Carrow_forwardC28. Do the following examples describe directional, disruptive, balancing, or stabilizing selection? A. Polymorphisms in snail color and banding pattern as described in Figure 24.13 B. Thick fur among mammals exposed to cold climates C. Birth weight in humans D. Sturdy stems and leaves among plants exposed to windy climatesarrow_forward
- Which of the following is NOT a correct statement regarding the neutral-mutation explanation for the high levels of genetic variation? A. Most genetic variation observed is adaptively neutral. B. Natural selection plays a lesser role in maintaining genetic variation. C. When natural selection occurs it leads to a decrease in genetic variation. D. Genetic variation is maintained mainly via the random effects of genetic drift.arrow_forwardScientists have concluded that the AS genotype as an adaptation for survival in Africa. Support the conclusion in terms of natural selection A. The frequency of the AS allele increases proportionately to the number of Africans in the population B. Because Malaria does not exist in the U.S and the AS allele does not provide any advantage to survival there. C. As the frequency of Malaria increases so does the frequency of the AS allele combination as it protects against getting Malaria D. Those without the AS genotype die out due to sickle cell disease; the populations left with a greater allelic frequency of the AS genotypearrow_forwardWhich of the following is NOT true of stabilising selection a. it occurs when inidivuals with extreme trait values have lower fitness than those with intermediate trait values. b. it keeps the mean close (or moves it closer) to the optimum value c. it can result from opposing directional selection, such as when early flowering makes flowers susceptible to herbivores, but late flowering reduces the availability of pollinators. d. it does not improve the fitness of the population to the environment. e. it decreases the range of variation in the populationarrow_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
- Human Anatomy & Physiology (11th Edition)BiologyISBN:9780134580999Author:Elaine N. Marieb, Katja N. HoehnPublisher:PEARSONBiology 2eBiologyISBN:9781947172517Author:Matthew Douglas, Jung Choi, Mary Ann ClarkPublisher:OpenStaxAnatomy & PhysiologyBiologyISBN:9781259398629Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa StouterPublisher:Mcgraw Hill Education,
- Molecular Biology of the Cell (Sixth Edition)BiologyISBN:9780815344322Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter WalterPublisher:W. W. Norton & CompanyLaboratory Manual For Human Anatomy & PhysiologyBiologyISBN:9781260159363Author:Martin, Terry R., Prentice-craver, CynthiaPublisher:McGraw-Hill Publishing Co.Inquiry Into Life (16th Edition)BiologyISBN:9781260231700Author:Sylvia S. Mader, Michael WindelspechtPublisher:McGraw Hill Education
Human Anatomy & Physiology (11th Edition)
Biology
ISBN:9780134580999
Author:Elaine N. Marieb, Katja N. Hoehn
Publisher:PEARSON
Biology 2e
Biology
ISBN:9781947172517
Author:Matthew Douglas, Jung Choi, Mary Ann Clark
Publisher:OpenStax
Anatomy & Physiology
Biology
ISBN:9781259398629
Author:McKinley, Michael P., O'loughlin, Valerie Dean, Bidle, Theresa Stouter
Publisher:Mcgraw Hill Education,
Molecular Biology of the Cell (Sixth Edition)
Biology
ISBN:9780815344322
Author:Bruce Alberts, Alexander D. Johnson, Julian Lewis, David Morgan, Martin Raff, Keith Roberts, Peter Walter
Publisher:W. W. Norton & Company
Laboratory Manual For Human Anatomy & Physiology
Biology
ISBN:9781260159363
Author:Martin, Terry R., Prentice-craver, Cynthia
Publisher:McGraw-Hill Publishing Co.
Inquiry Into Life (16th Edition)
Biology
ISBN:9781260231700
Author:Sylvia S. Mader, Michael Windelspecht
Publisher:McGraw Hill Education
Genetic Variation and Mutation | 9-1 GCSE Science Biology | OCR, AQA, Edexcel; Author: SnapRevise;https://www.youtube.com/watch?v=bLP8udGGfHU;License: Standard YouTube License, CC-BY