Certain genes determine sex, fertility, and viability in Drosophila, and mutations in these genes affect the two sexes differently. Class the descriptions below based on their occurrence in XY or XX flies. Some descriptions may be used in both categories. The expressed form of Dsx activates maleness genes and represses femaleness genes. XY XX Null mutations in the dsx gene result in an intersex phenotype. Loss-of-function mutations in the tra gene have no effect on phenotype. Sxl is expressed in early embryogenesis from the establishment promoter. Flies that produce Fru-M in brain cells from a transgene perform a mating dance and specifically court females. Loss-of-function mutations in the fru gene result in flies who court both males and females. Sxl regulates splicing of its own RNA to produce a functional protein. The expressed form of Dsx activates femaleness genes and represses maleness genes. Loss-of-function mutations in the Sxl gene have no effect on phenotype. Reset

Certain genes determine sex, fertility, and viability in Drosophila, and mutations in these genes affect the two sexes differently. Class the descriptions below based on their occurrence in XY or XX flies. Some descriptions may be used in both categories. The expressed form of Dsx activates maleness genes and represses femaleness genes. XY XX Null mutations in the dsx gene result in an intersex phenotype. Loss-of-function mutations in the tra gene have no effect on phenotype. Sxl is expressed in early embryogenesis from the establishment promoter. Flies that produce Fru-M in brain cells from a transgene perform a mating dance and specifically court females. Loss-of-function mutations in the fru gene result in flies who court both males and females. Sxl regulates splicing of its own RNA to produce a functional protein. The expressed form of Dsx activates femaleness genes and represses maleness genes. Loss-of-function mutations in the Sxl gene have no effect on phenotype. Reset

Human Heredity: Principles and Issues (MindTap Course List)

11th Edition

ISBN:9781305251052

Author:Michael Cummings

Publisher:Michael Cummings

Chapter7: Development And Sex Determination

Section: Chapter Questions

Problem 12QP: Mutations Can Uncouple chromosomal Sex from Phenotypic Sex Discuss whether the following individuals...

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