Question: Q1. In mice, the dominant allele Gs of the X-linked gene Greasy produces shiny fur, while the rec…


Q1. In mice, the dominant allele Gs of the X-linked gene Greasy produces shiny fur, while the recessive wild-type Gs allele determines normal fur. The dominant allele Bhd of the X linked Broadhead gene causes skeletal abnormalities including broad heads and snouts, while the recessive wild-type Bhd allele yields normal skeletons. Female mice heterozygous for the two alleles of both genes were mated with wild-type males. Among 100 male progeny of this cross, 49 had shiny fur, 48 had skeletal abnormalities, 2 had shiny fur and skeletal abnormalities, and 1 was wild type a. Diagram the cross described and calculate the distance between the two genes b. What would have been the results if you had counted 100 female progeny of the cross? (Question 5 from your text) Q2. In Drosophila, males from a true-breeding stock with raspberry-colored eyes were mated to females from a true-breeding stock with sable-colored bodies. In the Fi generation, all the females had wild-type eye and body color, while all the males had wild-type eye color but sable- colored bodies. When Fi males and females were mated, the F2 generation was composed of 216 females with wild-type eyes and bodies, 223 females with wild-type eyes and sable bodies, 191 males with wild-type eyes and sable bodies, 188 males with raspberry eyes and wild-type bodies 23 males with wild-type eyes and bodies, and 27 males with raspberry eyes and sable bodies. Explain these results by diagramming the crosses, and calculate any relevant map distances. Question 6 from your text) Q3. CC DD and cc dd individuals were crossed to each other, and the Fi generation was backcrossed to the cc dd parent. 997 Cc Dd, 999 cc dd, 1 Cc dd, and 3 cc Dd offspring resulted. a. How far apart are the c and d loci? b. What progeny and in what frequencies would you expect to result from testcrossing the Fı generation from a CC dd x cc DD cross to cc dd.? In a typical meiosis, how many crossovers occur between genes C and D? d. c. Assume that the C and D loci are on the same chromosome, but the offspring from the testcross described in part (b) were 498 Cc Dd, 502 cc dd, 504 Cc dd, and 496 cc Dd. How would your answer to part (c) change? (Question 8 from your text) Q4. Cinnabar eyes (cn) and reduced bristles (rd) are autosomal recessive characters in Drosophila. A homozygous wild-type female was crossed to a reduced, cinnabar male, and the Fi males were then crossed to the Fi females to obtain the F2. Of the 400 F2 offspring obtained, 292 were wild tyne. 9 were cinnahar 7 were reduced, and 92 were reduced, cinnahar Exnlain

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Q1. In mice, the dominant allele Gs of the X-linked gene Greasy produces shiny fur, while the recessive wild-type Gs allele determines normal fur. The dominant allele Bhd of the X linked Broadhead gene causes skeletal abnormalities including broad heads and snouts, while the recessive wild-type Bhd allele yields normal skeletons. Female mice heterozygous for the two alleles of both genes were mated with wild-type males. Among 100 male progeny of this cross, 49 had shiny fur, 48 had skeletal abnormalities, 2 had shiny fur and skeletal abnormalities, and 1 was wild type a. Diagram the cross described and calculate the distance between the two genes b. What would have been the results if you had counted 100 female progeny of the cross? (Question 5 from your text) Q2. In Drosophila, males from a true-breeding stock with raspberry-colored eyes were mated to females from a true-breeding stock with sable-colored bodies. In the Fi generation, all the females had wild-type eye and body color, while all the males had wild-type eye color but sable- colored bodies. When Fi males and females were mated, the F2 generation was composed of 216 females with wild-type eyes and bodies, 223 females with wild-type eyes and sable bodies, 191 males with wild-type eyes and sable bodies, 188 males with raspberry eyes and wild-type bodies 23 males with wild-type eyes and bodies, and 27 males with raspberry eyes and sable bodies. Explain these results by diagramming the crosses, and calculate any relevant map distances. Question 6 from your text) Q3. CC DD and cc dd individuals were crossed to each other, and the Fi generation was backcrossed to the cc dd parent. 997 Cc Dd, 999 cc dd, 1 Cc dd, and 3 cc Dd offspring resulted. a. How far apart are the c and d loci? b. What progeny and in what frequencies would you expect to result from testcrossing the Fı generation from a CC dd x cc DD cross to cc dd.? In a typical meiosis, how many crossovers occur between genes C and D? d. c. Assume that the C and D loci are on the same chromosome, but the offspring from the testcross described in part (b) were 498 Cc Dd, 502 cc dd, 504 Cc dd, and 496 cc Dd. How would your answer to part (c) change? (Question 8 from your text) Q4. Cinnabar eyes (cn) and reduced bristles (rd) are autosomal recessive characters in Drosophila. A homozygous wild-type female was crossed to a reduced, cinnabar male, and the Fi males were then crossed to the Fi females to obtain the F2. Of the 400 F2 offspring obtained, 292 were wild tyne. 9 were cinnahar 7 were reduced, and 92 were reduced, cinnahar Exnlain

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