You are interested in three linked Drosophila genes (B, R, and D) to understand their relative location along a chromosome. You perform a test cross between parents with known genotypes BbRrDd (phenotype BRD) and bbrrdd (phenotype brd). The BbRrDd individual was the offspring of two completely homozygous parents (BBRRDD and bbrrdd). The number of offspring with each phenotype are shown in the table below. Note that phenotypes are written as italicized letters representing dominant (capital) or recessive (lower case) phenotypes. For example, the individual BrD has the dominant phenotypes for genes B and D and the recessive phenotype for gene R. BRd Brd bRd |65 Phenotype BRD brd BrD 68 bRD 137 brD |14 # Offspring 281 22 121 292 Total Number of Offspring: 1,000 Based on the data above, which of these genes (B, R, or D) is in the middle of the other two, along the chromosome? R O These three genes are not all on the same chromosome You cannot determine this location given only offspring phenotype numbers

You are interested in three linked Drosophila genes (B, R, and D) to understand their relative location along a chromosome. You perform a test cross between parents with known genotypes BbRrDd (phenotype BRD) and bbrrdd (phenotype brd). The BbRrDd individual was the offspring of two completely homozygous parents (BBRRDD and bbrrdd). The number of offspring with each phenotype are shown in the table below. Note that phenotypes are written as italicized letters representing dominant (capital) or recessive (lower case) phenotypes. For example, the individual BrD has the dominant phenotypes for genes B and D and the recessive phenotype for gene R. BRd Brd bRd |65 Phenotype BRD brd BrD 68 bRD 137 brD |14 # Offspring 281 22 121 292 Total Number of Offspring: 1,000 Based on the data above, which of these genes (B, R, or D) is in the middle of the other two, along the chromosome? R O These three genes are not all on the same chromosome You cannot determine this location given only offspring phenotype numbers

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter15: Genomes And Genomics

Section: Chapter Questions

Problem 2QP: Hemophilia and color blindness are both recessive conditions caused by genes on the X chromosome. To...

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The allele b gives Drosophila flies a black body and b+ gives brown, the wild-type phenotype. The allele wx of a separate gene gives waxy wings and wx+ gives non-waxy, the wild-type phenotype. The allele cn of a third gene gives cinnabar eyes and cn+ gives red, the wild-type phenotype. A female heterozygous for these three genes is testcrossed, and 1000 progeny are classified with the following phenotypes. 382 cinnabar 379 black, waxy 69 waxy, cinnabar 67 black 48 waxy 44 black, cinnabar 5 wild type 6 black, waxy, cinnabar Based on this data, what is the correct map of these genes in terms of order and distance?
The genetic map was based on crosses in Drosophila involving the three sex-linked genes a, b and c. “a” gives red eyes, “b” gives normal wings and “c” gives black body. The recombination frequencies between these genes are as follows; a and b is 23.8, b and c is 2.6 and a and c is 28.1, respectively. Could you draw a basic genetic map based on distance between these genes using dots to show distance(s)? Could you make one fundamental comment using these distances based on genetic linkage?
You design Drosophila crosses to provide recombinationdata for gene a, which is located on the chromosome shownin Figure 15.12. Gene a has recombination frequencies of14% with the vestigial wing locus and 26% with the browneye locus. Approximately where is a located along thechromosome?
Part A: If the two genes are 30 mu apart and the plant is (AB/ab), what proportion of gametes from a single plant will be AB? Enter your answer as a decimal to three places (for example: 0.120). Part B: If the two genes are 30 mu apart and the plant is (AB/ab), what proportion of gametes from a single plant will be Ab? Part C: If the two genes are 30 mu apart and the plant is (AB/ab), what proportion of gametes from a single plant will be aB? Part D: If the two genes are 30 mu apart and the plant is (AB/ab), what proportion of gametes from a signal plant will be ab?
Phenotypically wild-type F1 female Drosophila, whose mothers had light eyes (lt) and fathers had straw (stw) bristles, produced the following offspring when crossed to homozygous light eyed, straw bristled males: Phenotype Number light-straw 140 wild-type 160 light 360 straw 340 Total 1000 Compute the map distance between the light and straw loci. Group of answer choices 70 map units 3 map units 7 map units 0.03 map units 30 map units
In Drosophila the genes A B D are linked. You cross a strain that is homozygous for d with a strain that is homozygous for ab. Below are the phenotypes and progeny of a test cross. Give the correct order of the genes in the chromosome and determine the map distances between genes. Phenotype Number ABd 389 abD 413 ABD 60 abd 68 aBd 29 AbD 34 Abd 3 aBD 4
Female drosophila heterozygous for ebony (e+/e), scarlet (st+/st) and spineless (ss+/ss) were test crossed and the following progeny were obtained Wild type 67 Ebony 8 Ebony, scarlet 68 Ebony, spineless 347 Ebony, scarlet, spineless 78 Scarlet 368 Scarlet, spineless 10 Spineless 54 Are these genes linked? Justify your answer with a chi square test Write the genotypes of the flies involved in the parental cross and test cross What is the map distance between the loci for ebony and scarlet? What is the map distance between the loci for ebony and spineless? What is the correct order of the genes on the chromosome? Calculate the coefficient of coincidence and the interference
In Drosophila flies, the allele b gives a black body, and the allele b+ gives brown, the wild-typephenotype. The allele wx of a separate gene gives waxy wings, and wx+ gives non-waxy. The allele cn ofa third gene gives cinnabar eyes, and cn+ gives red. A female heterozygous for these three genes istestcrossed, and 745 progenies are produced which are phenotypically classified as follows:5 b+ wx+ cn+4 b wx cn53 b+ wx cn 49 b wx+ cn+287 b+ wx+ cn279 b wx cn+ 33 b+ wx cn+35 b wx+ cn Make a linkage map of the three genes. Compute for interference and explain what the derived valuemeans. Show complete solutions to support your answers.
The production of eye-color pigment in Drosophila requires the dominant allele A. The dominant allele P of a second independent gene turns the pigment to purple, but its recessive allele leaves it red. A fly producing no pigment has white eyes. Two pure lines were crossed with the following results:P red-eyed female white-eyed maleF1 purple-eyed femalesred-eyed malesF1 F1purple eyed 38red eyed 38white eyed 28F both males and females: 2Explain this mode of inheritance, and show the genotypes of the parents, the F1, and the F2.
From a Drosophila testcross, the number of each phenotype obtained was as follows: W+ m f+ 218 W m+ f 236 W+ m+ f 168 W m f+ 178 W+ m f 95 W m+ f+ 101 W+ m+ f+ 3 W m f 1 Total, 1000 Construct a genetic map.
The F1 flies described in question 1 were mated with brown-eyed flies from a true-breeding line. What phenotypes would you expect the offspring to have? (a) all with red eyes (b) all with brown eyes (c) half with red eyes and half with brown eyes (d) red-eyed females and brown-eyed males (e) brown-eyed females and red-eyed males
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?