A 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.

A 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.

Name: A test cross between a plant of genotype PpSs and the tester white pla
Uploaded: 2024-03-20T06:43:04.000Z
Channel: Bartleby
Description: A 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

Concepts of Biology

1st Edition

ISBN:9781938168116

Author:Samantha Fowler, Rebecca Roush, James Wise

Publisher:Samantha Fowler, Rebecca Roush, James Wise

Chapter8: Patterns Of Inheritance

Section: Chapter Questions

Problem 5RQ: Imagine that you are performing a cross involving seed texture in garden pea plants. You cross...

See similar textbooks

Similar questions

Figure 8.10 In pea plants, purple flowers (P) are dominant to white (p), and yellow peas (Y) are dominant to green (y). What are the possible genotypes and phenotypes for a cross between PpYY and ppYy pea plants? How many squares would you need to complete a Punnett square analysis of this cross?
In the tomato, yellow flowers (Y) is dominant to white flowers (y). A true-breeding yellow flowered strain is crossed with a true-breeding white flowered strain.A. If the F1 generation is self crossed, what will be the genotypes and phenotypes of the progeny and in what portions are they expected? B. If an F1 plant were crossed with a plant from true-breeding white flowered strain, what will be the genotypes and phenotypes of the progeny and in what portions are they expected?
In tomatoes, tall (D) is dominant over dwarf (d) and smooth fruit (P) is dominant over pubescent fruit (p), which is covered with fine hairs. A farmer has two tall and smooth tomato plants, which we will call plant A and plant B. The farmer crosses plants A and B with the same dwarf and pubescent plant and obtains the following numbers of progeny: Q. Explain why different proportions of progeny are produced when plant A and plant B are crossed with the same dwarf pubescent plant.
A 3-inch plant was crossed with a 15-inch plant, and all F1 plants were 9 inches. The F2 plants exhibited a “normal distribution,” with heights of 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, and 15 inches. (a) What ratio will constitute the “normal distribution” in the F2? (b) What will be the outcome if the F1 plants are testcrossed with plants that are homozygous for all nonadditive alleles?
Assume the height in a particular plant is determined by two pairs of unlinked polygenes, each effective allele contributes 5cm to a base height of 10cm.a. What are the heights of each parent?b. What height is to be expected in the F1 if there are no environmental effects?c. What is the expected phenotypic ratio in the F2
Assume that in a series of experiments, plants with round seeds were crossed with plants with wrinkled seeds and the following offspring were obtained: 220 round and 180 wrinkled. (a) What is the most probable genotype of each parent?(b) What genotypic and phenotypic ratios are expected?(c) Based on the information provided in part (b) above, what are the expected (theoretical) numbers of progeny (400 total) of each phenotypic class?
In garden peas, long stems are dominant to short stems, and yellow seeds are dominant to green seeds. 100 long/yellow pea plants, all of which had one short/green parent, are interbred (bred to each other). 1600 progeny result. Please answer the following questions about these progenies. A. Assuming that these two genes are unlinked, about how many long/green pea plants would you expect to find among the offspring? B. What ratio of yellow to green seed color would you expect among the offspring? C. What would you expect the overall phenotypic ratio among the 1600 offspring to be (taking into consideration both traits)?
shows the results of a dihybrid cross involving seed shape and seed color. a. What proportion of the round and yellow F2 progeny from this cross is homozygous at both loci? b. What proportion of the round and yellow F2 progeny from this cross is homozygous at least at one locus?
Assume that plant weight is determined by a pair of alleles at each of two independently assorting loci (A and a, B and b) that are additive in their effects. Further assume that each allele represented by an uppercase letter contributes 4 g to weight and that each allele represented by a lowercase letter contributes 1 g to weight. a. If a plant with genotype AA BB is crossed with a plant with genotype aa bb, what weights are expected in the F1 progeny? b. What is the distribution of weight expected in the F2 progeny?
. In common wheat, Triticum aestivum, kernel color is determined by multiply duplicated genes, each with an Rand an r allele. Any number of R alleles will give red, anda complete lack of R alleles will give the white phenotype.In one cross between a red pure line and a white pureline, the F2 was 6463 red and 641 white.a. How many R genes are segregating in this system?b. Show the genotypes of the parents, the F1, and the F2.c. Different F2 plants are backcrossed with the whiteparent. Give examples of genotypes that would give thefollowing progeny ratios in such backcrosses: (1) 1 red :1 white, (2) 3 red :1 white, (3) 7 red :1 white.d. What is the formula that generally relates thenumber of segregating genes to the proportion of redindividuals in the F2 in such systems?
Assume that the trihybrid cross AABBrr x aabbRR is made in a plant species. Assume that A and B are dominant alleles, but there is no dominance effect of alleles at the R locus. a) How many different gametes are possible in the F1generation? What are the genotypes of these gametes? b) What is the probability of the parental aabbRR genotype in the F2 progeny? c) What proportion of the F2 progeny would be expected to be homozygous for all three genes?
You self-fertilize an F1 plant to produce the F2 generation. Based on Mendelian principles of inheritance, what fraction of the F2 generation do you expect to be short with round, green seeds? HINT: Solving this problem will require a very large Punnett square (8 x 8), but you can easily solve it using the Multiplication Rule