Genetics: From Genes to Genomes
6th Edition
ISBN: 9781259700903
Author: Leland Hartwell Dr., Michael L. Goldberg Professor Dr., Janice Fischer, Leroy Hood Dr.
Publisher: McGraw-Hill Education
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Chapter 12, Problem 15P
Drosophila geneticists have isolated many mutations that modify position-effect variegation. Dominant suppressors of variegation [Su(var)s] cause less frequent inactivation of genes brought near heterochromatin by chromosome rearrangements, while dominant enhancers of variegation [E(var)s] cause more frequent inactivation of such genes.
| a. | What effects would each of these two kinds of mutations have on position-effect variegation of the white gene in Drosophila (that is, would the eyes be more red or more white)? |
| b. | Assuming that these Su(var) and E(var) mutations are loss-of-function (null) alleles in the corresponding genes, what kinds of proteins do you think these genes might encode? |
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Chapter 12 Solutions
Genetics: From Genes to Genomes
Ch. 12 - For each of the terms in the left column, choose...Ch. 12 - Many proteins other than histones are found...Ch. 12 - What difference exists between the compaction of...Ch. 12 - What is the role of the core histones in...Ch. 12 - a. About how many molecules of histone H2A would...Ch. 12 - The enzyme micrococcal nuclease can cleave...Ch. 12 - a. What letters are used to represent the short...Ch. 12 - About 2000 G bands are visible in a...Ch. 12 - Suppose you performed a fluorescence in situ...Ch. 12 - Which of the following would be suggested by a...
Ch. 12 - For each of the following pairs of chromatin...Ch. 12 - a. Drosophila b. Humans Give examples of...Ch. 12 - One histone modification that is seen consistently...Ch. 12 - Recently, scientists constructed a transgene that...Ch. 12 - Drosophila geneticists have isolated many...Ch. 12 - On the following figures, genes A and B are on the...Ch. 12 - Prob. 17PCh. 12 - The first page of this chapter displays photos of...Ch. 12 - The human genome contains about 3 billion base...Ch. 12 - The mitotic cell divisions in the early embryo of...Ch. 12 - In an experiment published in the journal Cell in...Ch. 12 - a. What DNA sequences are found at the telomeres...Ch. 12 - Prob. 23PCh. 12 - a. In a fluorescent in situ hybridization FISH...Ch. 12 - If you are comparing the two telomeres in each...Ch. 12 - a. What DNA sequences are commonly found at human...Ch. 12 - On the graphs presented in Problem 21, no data is...Ch. 12 - Prob. 29PCh. 12 - Prob. 30PCh. 12 - In the 1920s, Barbara McClintock, later a Nobel...Ch. 12 - Give at least one example of a chromosomal...Ch. 12 - Cornelia de Lange syndrome CdLS is a rare human...Ch. 12 - a. Give at least three examples of types of...Ch. 12 - A number of yeast-derived elements were added to...Ch. 12 - Prob. 36PCh. 12 - The completely synthetic yeast chromosome Syn III...
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