Concept explainers
HOW DO WE KNOW?
Population geneticists study changes in the nature and amount of
(a) How do we know how much genetic variation is in a population?
(b) How do geneticists detect the presence of genetic variation as different alleles in a population?
(c) How do we know whether the genetic structure of a population is static or dynamic?
(d) How do we know when populations have diverged to the point that they form two different species?
(e) How do we know the age of the last common ancestor shared by two species?
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Essentials of Genetics (9th Edition) - Standalone book
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- How Can We Measure Allele Frequencies in Populations? The MN blood group is a single-gene, two-allele system in which each allele is codominant. Why are such codominant alleles ideal for studies of allele frequencies in a population?arrow_forwardWhy is genetic drift more significant in small populations? Why does it take longer for genetic drift to cause allele fixation in large populations than in small ones?arrow_forwardIf the frequency of a dominant allele “B” in a population is 80%, and assuming genetic equilibrium in this population, what percentage of the offspring in the next generation could be expected to have the heterozygous genotype?arrow_forward
- you (should have) learned that selection alone cannot purge a population of the very last copy of a deleterious allele. If selection is unable to do so, which of the remaining mechanisms (of the five Hardy-Weinberg) assumptions is MOST LIKELY to do so? Justify your answer. That is, why is the mechanism you picked the most likely to get rid of that last copy of a harmful allele?arrow_forwardIf 80% of a population has a heterozy gous phenotype, and 16% of that population shows a recessive phenotype, is that population in Hardy - Weinberg equilibrium? In other words, does the population obey the rules of H - W? Perform a statistical analysis to determine your final answer.arrow_forwardUnder what scenaries is genetic drift most potent as an evolutionary process? how do factors like population size and initial allele frequences affect likelihood of an allele being lost from a population (or becoming fixed)?arrow_forward
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