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A true-breeding pea plant with round and Page 44 green seeds was crossed to a true-breeding plant with wrinkled and yellow seeds. Round and yellow seeds are the dominant traits. The
A. An
B. Three out of three
C. Five
D. An
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Genetics: Analysis and Principles
- If a cross is made between two plants that are heterozygous for two traits (AaBb), then their offspring should follow the 9:3:3:1 ratio. In this case, A is the dominant allele for purple leaves, and B is the dominant allelle for curly roots. If the two parents were crossed to yield 320 progeny, approximately how many plants with purple leaves and curly roots would you expect? Group of answer choices a.180 b.225 c.25 d.50 As part of a lab experiment, you create a two-locus cross between two plants, and you expect to see a 8:4:2:2 ratio of offspring. You determine the phenotype for 160 offspring, and find the proportions 84:38:19:19. If you use a chi-square test to determine whether the offspring do indeed fit this pattern, how many degrees of freedom would the test have? Group of answer choices a.2 b.3 c.83 d.4arrow_forwardA test cross between a plant of genotype PpSs and the tester white plant with wrinkled seed coat (ppss) gives the following numbers of progeny in four phenotypic types. 14:87:83:16 (purple flower + smooth seed coat: purple flower + wrinkled seed coat: white flower + smooth seed coat: white flower + wrinkled seed coat). a. What is the expected ratio of progeny phenotypes assuming independent assortment of alleles? b. Explain how ratios of progeny show that the two genes are linked. c. How many map units separate the purple and smooth genes? Show your calculations. d. What is the “parental” genotype of the heterozygous parent? (i.e. Which alleles of the P and S loci are present on each of the two chromosomes of the doubly heterozygous parent of this test cross?)arrow_forwardSunflowers with flowers 10 cm in diameter are crossed with a plant that has 16 cm flowers. The F1 plants have flowers 13 cm in diameter. In the F2 generation, 4 flowers are 10 cm in diameter and 4 are 16 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes.a) Assuming that the alleles that contribute to flower diameter act additively, how many genes control flower size? b) How much does each additive allele contribute to flower diameter? c) What size flower makes up the largest phenotypic class?arrow_forward
- Sunflowers with flowers 10 cm in diameter are crossed with a plant that has 16 cm flowers. The F1 plants have flowers 13 cm in diameter. In the F2 generation, 4 flowers are 10 cm in diameter and 4 are 16 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes.a) Assuming that the alleles that contribute to flower diameter act additively, how many genes control flower size? b) How much does each additive allele contribute to flower diameter?(show work) c) What size flower makes up the largest phenotypic class?(show work)arrow_forwardIn a monohybrid cross with garden peas, you start with a strain with round seeds and a strain with wrinkled seeds and all the Fls have round seeds. If you let this F1 generation self-pollinate, and you get 300 F2 plants. Out of these, 190 have round seeds and 110 have wrinkled seeds. a). What statistical test do you use to find out if these numbers fit into the expected phenotypic ratio in the F2 of a monohybrid cross?"arrow_forwardIn the pearl-millet plant, color is determined by three alleles at a single locus: Rp1 (red), Rp2 (purple), and rp (green). Red is dominant over purple and green, and purple is dominant over green (Rp1 > Rp2 > rp). Give the expected phenotypes and ratios of offspring produced by the following crosses. a. Rp1/ Rp2 × Rp1/ rp b. Rp1/ rp × Rp2/ rp c. Rp1/ Rp2 × Rp1/ Rp2 d. Rp2/ rp × rp/ rp e. rp/ rp × Rp1/ Rp2arrow_forward
- In summer squash, white fruit color (W) is dominant over yellow fruit color (w) and disk-shaped fruit (D) is dominant over sphere-shaped fruit (d).. If a squash plant true-breeding for white, disk-shaped fruit is crossed with a plant true-breeding for yellow, sphere-shaped fruit, what will the phenotypic and genotypic ratios be for: a. the F1 generation? b. the F2 generation? You must show the Punnett Square for the F2 generation!arrow_forwardSunflowers with flowers 10 cm in diameter are crossed with a plant that has 16 cm flowers. The F1 plants have flowers 13 cm in diameter. In the F2 generation, 4 flowers are 10 cm in diameter and 4 are 16 cm in diameter. Between these are 5 phenotypic classes with diameters intermediate to those at the extremes.How much does each additive allele contribute to flower diameter?(show work) What size flower makes up the largest phenotypic class?(show work)arrow_forwardA variety of opium poppy (Papaver somniferum L.) with lacerate leaves was crossed with a variety that has normal leaves. All the F1 had lacerate leaves. Two F1 plants were interbred to produce the F2. Of the F2, 249 had lacerate leaves and 16 had normal leaves. Give genotypes for all the plants in the P, F1, and F2 generations. Explain how lacerate leaves are determined in the opium poppy.arrow_forward
- Leaf color and stem length in a certain species of diploid flowers are controlled separately by the R and S locus. The R allele (dominant) results in red leaves while r results in yellow leaves. S (dominant) results in short stems and s results in long stems. A cross is performed between a true breeding long-stemmed red plant and a true breeding short- stemmed yellow plant. a. What is the genotype and phenotype of the resulting F1 plants? b. The resulting F1 plants are crossed with long-stemmed plants with yellow leaves. 100 offspring are collected from this cross, and the following phenotype counts are observed. phenotype long red short red count 43 8 long yellow short yellow 40 What are the corresponding genotypes for each of the four classes of the offspring from this cross? c. Using the information above, determine the genotype of the gametes contributed by "parent A" to each of the resulting offspring. Label the gamete types as parental or nonparental.arrow_forwardIn watermelons, bitter fruit (B) is dominant over sweet fruit (b), and yellow spots (S) are dominant over no spots (s). The genes for these two characteristics assort independently. A homozygous plant that has bitter fruit and yellow spots is crossed with a homozygous plant that has sweet fruit and no spots. The F1 are intercrossed to produce the F2. a. What are the phenotypic ratios in the F2? b. If an F1 plant is backcrossed with the bitter, yellow-spotted parent, what phenotypes and proportions are expected in the offspring? c. If an F1 plant is backcrossed with the sweet, unspotted parent, what phenotypes and proportions are expected in the offspring?arrow_forwardPurebred wrinkled, green-seeded pea plants were crossed with purebred round, yellow-seeded plants. The F1, all of which had round and yellow seeds, were then self-crossed resulting in the following F2: 172 plants with round and yellow seeds, 55 plants with round and green seeds, 58 plants with wrinkled and yellow seeds, and 15 plants with wrinkled and green seeds. Calculate the chi-square value and determine the p-value range. Which of the following are the correct chi-square values, p-value range, and whether you would accept or reject the hypothesis that these results are consistent with Mendelian predictions?arrow_forward
- Concepts of BiologyBiologyISBN:9781938168116Author:Samantha Fowler, Rebecca Roush, James WisePublisher:OpenStax College