Question

A normal Arabidopsis flower is comprised of four concentric whorls of structures, under the control of four organ-identity (homeotic) genes. The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels. a.) What knockout mutant would produce a flower with a sepal-sepal-carpel-carpel arrangement? b.) Mutations in Class C genes result in flowers that have a sepal, petal, petal, sepal organization. How does that support the concept that Genes A and C repress each other's expression? c.) Suggest a specific manner in which Gene A could repress Gene C. d.) Based on the phenotype you observe for the Class C mutant, predict the function of the protein of that normal gene and describe one type of experimental evidence (not just a Class C mutation phenotype) that would support your hypothesis. e.) You have a stock of wild-type plants that are producing flower buds. Through what technique would you document tissue-specific expression (mRNA) of the Class C gene? Be specific. f.) Through what specific technique would you show the localization of the Class C gene protein? g.) The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels. What would be the phenotype of the four flower whorls if the expression of class B genes is inhibited in the second whorl, but not in the third whorl? h.) The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels. What would be the phenotype of the four flower whorls if the expression of class C genes is inhibited in the third whorl, but not in the fourth whorl? i.) A newly-discovered tropical flowering plant has a unique floral structure. Petal-like organs are in the outer two whorls (no sepals), and they surround a number of carpels, and stamens are in the center of the flower (unlike other flowering plants). Closely related species are dioecious, that is, they have male and female flowers on different individual plants. In those species, female plants bear flowers that resemble the new species but without the stamens. What type of genetic change could have resulted in the evolution of flowers in the new species?

          A normal Arabidopsis flower is comprised of four concentric whorls of structures, under the control of four organ-identity (homeotic) genes. The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels.

a.) What knockout mutant would produce a flower with a sepal-sepal-carpel-carpel arrangement?
b.) Mutations in Class C genes result in flowers that have a sepal, petal, petal, sepal organization. How does that support the concept that Genes A and C repress each other's expression?
c.) Suggest a specific manner in which Gene A could repress Gene C.
d.) Based on the phenotype you observe for the Class C mutant, predict the function of the protein of that normal gene and describe one type of experimental evidence (not just a Class C mutation phenotype) that would support your hypothesis.
e.) You have a stock of wild-type plants that are producing flower buds. Through what technique would you document tissue-specific expression (mRNA) of the Class C gene? Be specific.
f.) Through what specific technique would you show the localization of the Class C gene protein?
g.) The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels. What would be the phenotype of the four flower whorls if the expression of class B genes is inhibited in the second whorl, but not in the third whorl?
h.) The wild-type flower phenotype of the four whorls is: 1-sepals, 2-petals, 3-stamens, 4-carpels. What would be the phenotype of the four flower whorls if the expression of class C genes is inhibited in the third whorl, but not in the fourth whorl?
i.) A newly-discovered tropical flowering plant has a unique floral structure. Petal-like organs are in the outer two whorls (no sepals), and they surround a number of carpels, and stamens are in the center of the flower (unlike other flowering plants). Closely related species are dioecious, that is, they have male and female flowers on different individual plants. In those species, female plants bear flowers that resemble the new species but without the stamens. What type of genetic change could have resulted in the evolution of flowers in the new species?

Added by Jennifer F.

Question

Please give Ace some feedback