Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Textbook Question
Chapter 27, Problem 9EQ
A recessive lethal allele has achieved a frequency of 0.22 due to genetic drift in a very small population. Based on natural selection, how would you expect the allele frequencies to change in the next three generations? (Note: Your calculation can assume that genetic drift is not altering allele frequencies in either direction.)
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A recessive lethal allele has achieved a frequency of 0.22 due to genetic drift in a very small population. Based on natural selection, how would you expect the allele frequencies to change in the next three generations? Now: Your calculation can assume that genetic drift is not altering allele frequencies in either direction.
Polydactyly (being born with more than 5 fingers or toes) is caused by a dominant allele of a single gene. If the frequency of the recessive allele is 0.9 (or 90%) in a certain population, what percentage of the population would you expect to be heterozygotes? Assume this population is in Hardy-Weinberg equilibrium.
Note: In reality, there are other causes of polydactyly when it is accompanied by other disorders, so this problem is an over-simplification.
18%
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At 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?
Chapter 27 Solutions
Genetics: Analysis and Principles
Ch. 27.1 - A gene pool is a. all of the genes in a single...Ch. 27.1 - 2. In natural populations, most genes...Ch. 27.1 - A gene exists in two alleles designatedDandd. If...Ch. 27.1 - Prob. 4COMQCh. 27.2 - Which of the following is a factor that, by...Ch. 27.3 - 1. Darwinian fitness is a measure...Ch. 27.3 - 2. Within a particular population, darkly colored...Ch. 27.3 - 3. A population occupies heterogeneous...Ch. 27.3 - Prob. 4COMQCh. 27.4 - 1. Genetic drift is
a. a change in allele...
Ch. 27.4 - 2. Which of the following influences on genetic...Ch. 27.5 - Gene flow depends on a. migration. b. the ability...Ch. 27.6 - 1. Inbreeding is sexual reproduction between...Ch. 27.7 - The mutation rate is a. the likelihood that a new...Ch. 27.7 - 2. The transfer of an antibiotic resistance gene...Ch. 27.7 - Prob. 3COMQCh. 27 - 1. What is the gene pool? How is a gene pool...Ch. 27 - Prob. 2CONQCh. 27 - Prob. 3CONQCh. 27 - Prob. 4CONQCh. 27 - The termpolymorphismcan refer to both genes and...Ch. 27 - Prob. 6CONQCh. 27 - For a gene existing in two alleles, what are the...Ch. 27 - 8. In a population, the frequencies of two...Ch. 27 - The ability to roll your tongue is inherited as a...Ch. 27 - What evolutionary factors can cause allele...Ch. 27 - What is the difference between a neutral and an...Ch. 27 - Prob. 12CONQCh. 27 - Prob. 13CONQCh. 27 - Describe the similarities and differences among...Ch. 27 - 15. Is each of the following examples due to...Ch. 27 - Prob. 16CONQCh. 27 - Prob. 17CONQCh. 27 - 18. A group of four birds flies to a new location...Ch. 27 - 19. Describe what happens to allele frequencies as...Ch. 27 - With regard to genetic drift, are the following...Ch. 27 - When two populations frequently intermix due to...Ch. 27 - Two populations of antelope are separated by a...Ch. 27 - Prob. 23CONQCh. 27 - 24. Using the pedigree shown here, answer the...Ch. 27 - A family pedigree is shown here. A. What is the...Ch. 27 - 26. A family pedigree is shown here.
A. What is...Ch. 27 - Prob. 27CONQCh. 27 - Prob. 28CONQCh. 27 - 1. You will need to be familiar with the...Ch. 27 - You will need to refer to question 2 in More...Ch. 27 - Prob. 3EQCh. 27 - Prob. 4EQCh. 27 - You will need to refer to question 2 in More...Ch. 27 - Prob. 6EQCh. 27 - Prob. 7EQCh. 27 - In the Grants study of the medium ground finch, do...Ch. 27 - 9. A recessive lethal allele has achieved a...Ch. 27 - Among a large population of 2 million gray...Ch. 27 - In a donor population, the allele frequencies for...Ch. 27 - Prob. 12EQCh. 27 - Prob. 13EQCh. 27 - Prob. 14EQCh. 27 - 15. What would you expect to be the minimum...Ch. 27 - Discuss examples of positive and negative...Ch. 27 - Discuss the role of mutation in the origin of...Ch. 27 - Prob. 3QSDC
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