Concept explainers
In a test of his chromosome theory of heredity, Morgan crossed an F1 female Drosophila with red eyes to a male with white eyes. The F1 females were produced from Cross A shown in Figure 3.19. Predict the offspring Morgan would have expected under his hypothesis that the gene for eye color is on the X chromosome in fruit flies.
Learn your wayIncludes step-by-step video
Chapter 3 Solutions
Genetic Analysis: An Integrated Approach (3rd Edition)
Additional Science Textbook Solutions
Human Anatomy & Physiology
Concepts of Genetics (12th Edition)
Human Physiology: An Integrated Approach (8th Edition)
Campbell Biology in Focus (2nd Edition)
Microbiology: An Introduction
Fundamentals of Anatomy & Physiology Plus Mastering A&P with eText - Access Card Package (10th Edition) (New A&P Titles by Ric Martini and Judi Nath)
- In Drosophila, red eyes is the wild-type phenotype. There are several different genes that affect eye colour. One allele causes purple eyes, and a different allele causes sepia eyes. When flies with purple eyes were crossed with flies with sepia eyes, all of the F1 offspring had red eyes. The F1 offspring were allowed to mate with each other and the following data were obtained: 146 purple eyes201 sepia eyes444 red eyes Formulate a hypothesis that you think is consistent with the observed data. Test the goodness of fit between the data and your hypothesis.arrow_forwardYou have been given a virgin Drosophila female. You notice that the bristles on her thorax are much shorter than normal. You mate her with a normal male (with long bristles) and obtain the following F1 progeny1 3 short-bristled females, 1 3 long-bristled females, and 1 3 long-bristled males. A cross of the F1 long-bristled females with their brothers gives only long-bristled F2. A cross of short-bristled females with their brothers gives 1 3 short-bristled females, 1 3 long-bristled females, and 1 3 long-bristled males. Provide a genetic hypothesis to account for all these results, showing genotypes in every cross.arrow_forwardA mutation of Drosophila has a wing condition known as beaded. When a beaded fly was crossed with a pure-line normal fly, 53 beaded and 47 normal F1 's were produced. When two of the F, beaded flies were mated, 67 beaded and 33 normal F2's were produced. Explain the genetics of the beaded trait and give the genotypes of all P and F1 generation flies.arrow_forward
- Imagine Drosophila genes C, D, and E are autosomal genes located close to each other on the same chromosome (same assumptions as the first problem). You cross a C D E homozygote with a c d e homozygote, then cross the F1 females with a c d e homozygous male. Of 400 progeny, you observe the following phenotypes: 135 CDE 139 cde 22 cDE 18 Cde 42 CdE 38 cDe 3 cdE 3 CDe a. What is the order of the genes? Calculate the distance between genes and draw a map to get the final answer. Question 2 options: 1.CED 2. DEC 3. ECD 4. DCEarrow_forwardIn Drosophila the genes forked bristles (f and f+) and vermilion eyes (v and v+) are ~24 m.u. apart on the X chromosome. From a cross of f v / f+ v+ females with f v / y males, what % of the progeny do you expect to have the f+ v+ phenotypes? (Don’t let the X chromosome throw you off – this question is essentially asking what % of the female’s gametes will be f+ v+).arrow_forwardIn Drosophila,, the curled mutation (cu, chromosome 3, position 50.0) results in wings that curl up, while ebony (e, chromosome 3, position 70.7) results in a dark body. True breeding, wild type females are mated with true breeding males with curled wings and ebony bodies. Considering Drosophila notation, which of the following correctly diagrams the P1 cross? X X ++ e + + + O+ X + X + ■ + X + + + 3+ X X X X + + Y Y cu cu cu + cu cu J e e e e e (D e + cu cu (Darrow_forward
- The orange coat color allele in cats is located on the X chromosome and is one of two genes responsible for tortoiseshell coat color. Two true-breeding cats are crossed, a black male and an orange female. Considering the female kittens, how many X chromosomes would be silenced at the indicated developmental stages: primary oocyte, single-cell female embryo, and adult female somatic cell. Considering the female kittens, some interesting coat colors were found. The kitten named Elsa had one black patch and one orange patch. The kitten named Annika had ten black patches and ten orange patches. Explain why these sisters look different based on their development from a single-cell female embryo to the somatic cells of the kitten.arrow_forwardImagine a germ cell for an animal that is 2n=4. Gene A and B are found on chromosome one, and the cell is homozygous for A(AA) and heterozygous for Bb. Gene D is found on chromosome 2 and the germ cell is heterozygous for the Allee of the gene (Dd). Meiosis for this germ cell results in the following four gametes, and one crossing over event during meiosis ABD, ABd, AbD, Abd. Draw the chromosomes in cell during metaphase of meiosis 1. Make sure to include chromosomes, the allele in the correct locations on the chromosomes AFTER the crossing over event, and spindle fibers.arrow_forwardA female Drosophila with the mutant phenotype 'notched wings' was mated to a wild type male. Two-thirds of the progeny were female. Half of the females had notched wings and the other half had wild type wings and all the male progeny had wild type wings. When the notched progeny were mated to their wild type brothers, the same results were obtained. Explain.arrow_forward
- 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?arrow_forwardIn Drosophila, a heterozygous female for the X-linkedrecessive traits a, b, and c was crossed to a male that phenotypically expressed a, b, and c. The offspring occurred inthe following phenotypic ratios.+ b c 460a + + 450a b c 32+ + + 38a + c 11+ b + 9 No other phenotypes were observed.(a) What progeny phenotypes are missing? Why?arrow_forwardSET 2: In corn, the following allelic pairs have been identified in chromosome 3: +/b plant color booster vs. non-booster +/lg with ligule vs. without ligule +/v green plant vs. virescent A test cross between triple recessive plants and plants heterozygous for the three pairs gave the following progeny: + v lg 305 b + lg b v lg + + lg b v + 148 58 + + + 62 + y + 152 b + + 275 Total 1000 Calculate the parental and recombinant frequencies, the map distances between genes, and the coefficient of coincidence. Illustrate the gene map or sequence.arrow_forward
- Human Biology (MindTap Course List)BiologyISBN:9781305112100Author:Cecie Starr, Beverly McMillanPublisher:Cengage LearningHuman Heredity: Principles and Issues (MindTap Co...BiologyISBN:9781305251052Author:Michael CummingsPublisher:Cengage Learning