Concept explainers
Epidemiologic data on the population in the previous problem reveal that before the application of modern medical treatment, natural selection played a major role in shaping the frequencies of alleles. Heterozygous individuals have the highest relative fitness, and in comparison to heterozygotes, those who are
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GENETIC ANALYSIS: INTEGRATED - ACCESS
- You have collected and determined genotypes of 200 individuals from a population of thr fruit fly, Drosophila pseudoobscura. Your sequencing study revealed 20 individuals with genotype AA, 70 individuals with genotype Aa and 110 individuals with genotype aa. i) what are your theoretical expectations for the number of individuals with each genotype if the population is in Hardy-Weinberg equilibrium. ii) Based on the genotype counts observed, is there evidence that this population of fruit flies deviates from your theoretical expectations under Hardy-Weinberg equilibrium?arrow_forwardA sample of 100 individuals from a population that is dimorphic at the A locus has genotype counts as follows. AA: 30 Aa: 60 aa: 10 a) What are the allele frequencies in the population? b) What are the expected genotype frequencies, if the population were at HardyWeinberg equilibrium? c) Is the proportion of heterozygotes lower or higher than expected at Hardy-Weinberg equilibrium? What deviations from the assumptions of the model would best explain the observed difference?arrow_forwardYou are a scientist studying a population of beetles. Beetle color is controlled by two alleles at a single genetic locus. AA beetles are blue, Aa purple, and aa pink. You count 30 blue beetles, 10 purple beetles, and 40 pink beetles. a) What is the frequency of the A allele? [ Select ] b) What is the observed frequency of the Aa genotype? 1 Select ] c) Under Hardy-Weinberg equilibrium, what is the expected frequency of the aa gentoype? [ Select ] d) Is this beetle population evolving? I Select ]arrow_forward
- An autosomal locus has alleles A and a. The allele frequencies in a population at Hardy Weinberg equilibrium are p = Freq(A) = 0.5 q = Freq(a) = 0.5 What is the frequency of homozygous wild-type (AA) in this population? Enter a single number between 0 and 1, for example, 0.33arrow_forwarda.)If the frequency of an allele at a locus of interest is 0.57, what is the frequency of the genotype that is homozygous for this allele (that is, that genotype has two copies of this allele)? b.) If we know that the frequency of an allele at a locus of interest is 0.57, we have enough information to calculate the frequency of the related phenotypes in the population, assuming there are only two alleles.arrow_forwardln a population of turtles, there are yellow-green shells and green shells. The yellow shells are caused by a homozygous recessive gene and the green shells are caused by the dominant gene. Given the following data:AA = 340Aa = 270aa = 120 a) Calculate p and q. b) Use a chi square test to determine if these alleles are in Hardy-Weinberg equilibrium. Submit your answer as a pdf or doc file. Show your workarrow_forward
- What is the expected genotype frequency of the heterozygous genotype under the Hardy-Weinberg equation P = 0.7?arrow_forwardA population of wookies is polymorphic for the fur color, which is controlled by two loci. 230 have black hair, 64 have brown hair, and 32 have yellow hair. You test suspect that the epistatic interactions between the two loci are reponsible for this ratio and wish to test that hypothesis using a X^2 test. a) What is the most likely epistasis? b) Complete the following X^2 table. For the first three columns, enter your answer as intergers with no demical points. For the last column, enter your answer to two deimal points e.g 4.36 Fur Observed Expected O-E (O-E)^2 (O-E)^2/E Black 240 Brown 64 yellow 32 total 336 X^2arrow_forward(1 point) Humans with the genotypes DD and Dd show the Rh+ blood phenotype, whereas those with the genotype dd show the Rh- blood phenotype. In a sample of 400 Basques from Spain, 230 people were Rh+ and 170 people were Rh-. Assuming that this population is in Hardy-Weinberg proportions, what is the allele frequency of the allele D? (a) (a) 0.348 (answer) (b) (b) 0.652 (c) (c) 0.425 (d) (d) 0.575 (e) (e) 0.288 2. (2 points) In the Basque population mentioned above, what proportion of the Rh+ individuals would be expected to be heterozygote? (a) (a) 0.454 (b) (b) 0.789 (answer) (c) (c) 0.516 (d) (d) 0.250 (e) (e) 0.500 How is the answer for #2, b? please explainarrow_forward
- If a population is in Hardy-Weinberg equilibrium for the multiple alleles A+, A and a, whose frequencies are p= 0.60 for A+, q= 0.20 for A, and r = 0.20 for a, what percentage of the population is expected to be heterozygous?arrow_forwardIn another population, linkage disequilibrium was calculated to be D = 0.15, and the recombination rate between loci was r = 0.10. If there is no selection on this locus, and the population is mating randomly, what would be the predicted value of linkage disequilibrium after five generations? (show all calculations)arrow_forwardConsidering the Hardy-Weinberg theorem’s assumptions, which of the following statements is NOT correct? (Recall that there are certain assumptions that must be true in order for the Hardy-Weinberg theorem to accurately predict genotype ratios in the next generation.)a) The population must be very large so there random genetic drift will not occur.b) No natural selection can occur.c) Mating must be random.d) Individuals must migrate into and out of the population so that gene flow will occur.e) Mutations must not occur.arrow_forward
- Human Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning