WHAT IS LIFE? ACHIEVE ACCESS 1 TERM
5th Edition
ISBN: 9781319360702
Author: PHELAN
Publisher: INTER MAC
expand_more
expand_more
format_list_bulleted
Concept explainers
Videos
Question
Chapter 10, Problem 7MC
Summary Introduction
Introduction:
Stabilizing selection is one of the ways in which natural selection alters the allelic frequencies in a population.
Expert Solution & Answer
Want to see the full answer?
Check out a sample textbook solution
Students have asked these similar questions
If the X3 allele is undergoing positive selection, what will be the likely end result?
A There will be no individuals that are X3X3
B All individuals will be X1X3 or X2X3 because of the heterozygote advantage.
C The variance of the trait will stay the same, but the mean value will increase.
D The frequency of X3 will increase and it could potentially become fixed in the population.
e The allele frequency of X1 and X2 will stay the same, but the allele frequency of X3 will increase.
Saying that a quantitative trait follows a continuum means thata. the numerical value for the trait increases with the age ofthe individual.b. environmental effects are additive.c. the phenotypes for the trait are continuous and do not fallinto discrete categories.d. the trait continuously changes during the life of an individual.
Which 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 population
Chapter 10 Solutions
WHAT IS LIFE? ACHIEVE ACCESS 1 TERM
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
- A species of hummingbird feeds on nectar of a particular plant whose flowers form a long, skinny cup. Beak length is a heritable trait that varies among individual hummingbirds. The birds' beaks must be long enough to reach the nectar, but longer beaks are also heavier and make flying more costly in terms of energy. a. Which mode of selection is this hummingbird species experiencing? b. How does this mode of selection affect the mean and standard deviation over time?arrow_forwardA. Use the genotype frequencies, relative fitness, and the mean relative fitness to calculate the genotype frequencies expected to be found in the next generation Show your work, include 3 decimals. p2’ = 2pq’ = q2’ = B. Is natural selection acting in this population in this new environment?arrow_forwardAssuming 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_forward
- Illustrate (Draw) the following using the punnett square method:arrow_forwardConsider 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?arrow_forwardWhich of the following principles of selection are true for both the sickle cell and rock pocket mice examples? Check all that apply. (1 or more are correct). Group of answer choices A_The same genotype can have higher fitness in one environment, but lower fitness in another environment B-Some genotypes have higher fitness than other genotypes C-Some genotypes have lower fitness than other genotypesarrow_forward
- A type of bird on an island makes nests in both tree roots and in tree branches at various heights from the ground. A ground snake invades the island and eats eggs or chicks from nests in tree roots and low tree branches. Part A: What type of selection is operating on the height at which the bird places its nest? A. Stabilizing B. Balancing C. Directional D. Disruptive What's the rationale? What effect will this selection have on the trait phenotype (height of nest)? Answer based on chart linkedarrow_forwardWhen calculating heritability in finch beak size using parent/offspring data, we find that 70 percent of the variation in the trait is due to genetics. What might explain the remainder of the variation? Select all that apply. A. nutrition B. color C. precipitation D. stress E. rarity F. temperaturearrow_forward. A farmer have 2000 cows. A total of 1500 of the cows are browh coated and the rest are white coated. Allele B for the brown coat is dominant, while allele b for the white coat is recessive: Assume that the population of the cows is at genetic equilibrium and bred randomly. Calculate the frequency for the dominant and recessive alleles of the population. i. Calculate the genotype frequencies in the F1 generation if the cows are left to breed randomly. ii. If the farmer adds another 1000 homozygous dominant brown cows into the populations, calculate the new dominant allele frequency. ii. iv. State three conditions for the Hardy Weinberg equilibrium to be achieved.arrow_forward
- 1)You measure the effects of a single allele (A2) on fitness in two populations of the same plant species, Population X and Population Y. Population X lives at higher altitudes. The average excess of fitness of the A2 allele (aA2) in Population X is 1.21, and the average fitness of the population (w) is 1.0. Population Y lives at a lower altitude. The average excess of fitness of the A2 allele (aA2) in Population Y is -1.68 and the average fitness of the population (w) is 1.0 a) Which population is likely to experience faster evolution? Why? b) What do you predict will happen to the frequency of the A2 allele (pA2) in population X? c) What do you predict will happen to the frequency of the A2 allele (pA2) in population Y? d) Why do you think the average excess of fitness of the A2 allele is different in these two populations?arrow_forwardHigh values for heterozygosity (or expected heterozygosity) at a genetic locus in a population indicates that there is: a. A lot of genetic variation b. Little genetic variation c. A population not under HW equilibrium d. A large amount of homozygosityarrow_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_forward
arrow_back_ios
SEE MORE QUESTIONS
arrow_forward_ios
Recommended textbooks for you
Biology (MindTap Course List)BiologyISBN:9781337392938Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. BergPublisher:Cengage Learning
Biology (MindTap Course List)
Biology
ISBN:9781337392938
Author:Eldra Solomon, Charles Martin, Diana W. Martin, Linda R. Berg
Publisher:Cengage Learning
Mitochondrial mutations; Author: Useful Genetics;https://www.youtube.com/watch?v=GvgXe-3RJeU;License: CC-BY