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Genetics: From Genes To Genomes (6th International Edition)
6th Edition
ISBN: 9781260041217
Author: Leland Hartwell Dr., ? Michael L. Goldberg Professor Dr., ? Janice Fischer, ? Leroy Hood Dr.
Publisher: Mcgraw-Hill
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Textbook Question
Chapter 19, Problem 26P
In the 1920s, Arthur Boycott, working with the snail Limnaeaperegra, discovered the first maternal effect phenotype. Like most gastropods, the shell and internal organs of Limnaeaperegranormally coil to the right— a phenotype described as dextral. Boycott found a mutant whose body was mirror-image symmetrical to the wild type: The shell and internal body of the mutant coiled to the left—a phenotype called sinistral.
More recent studies have shown that sinistrality and dextrality are controlled by an autosomal maternal effect gene called s; the dominant s allele causes dextrality, and the recessive, loss-offunctions-allele causes sinistrality.
a. | Limnaeaare either hermaphrodites or males; the hermaphrodites can self-fertilize or they can mate with males. Suppose that a pure-breeding line of sinistral Limnaeahermaphrodites are crossed with males from a pure-breeding dextral line. What will be the phenotype of the progeny? |
b. | Answer part (a) for a cross performed in the opposite direction: dextral hermaphrodites crossed with sinistral males. |
c. | Describe the progeny |
d. | Suppose you now self the F2 from parts (a) and (b). What results would you expect in the F3 in each case? |
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Chapter 19 Solutions
Genetics: From Genes To Genomes (6th International Edition)
Ch. 19 - Match each of the terms in the left column to the...Ch. 19 - a. If you were interested in the role of a...Ch. 19 - Early C. elegans embryos display mosaic...Ch. 19 - Hypomorphic mutations in the wingless gene of...Ch. 19 - Prob. 5PCh. 19 - In 1932, H. J. Muller suggested a genetic test to...Ch. 19 - a. Explain how you could use worms transformed...Ch. 19 - Suppose you want to determine whether a particular...Ch. 19 - Sevenless is an unusual receptor protein in that...Ch. 19 - Suppose that you generated flies containing a...
Ch. 19 - Drosophila researchers have collected many strains...Ch. 19 - As an alternative to random mutagenesis,...Ch. 19 - A C. elegans nematode gene called par-1 helps to...Ch. 19 - The molecular identity of the fruit fly rugose...Ch. 19 - To determine the focus of action of boss,...Ch. 19 - Suppose a particular gene is required for early...Ch. 19 - Researchers have exploited Minute mutations in...Ch. 19 - Some ts alleles are temperature sensitive during...Ch. 19 - The following figure shows the temperature-shift...Ch. 19 - A temperature-sensitive allele of the gene...Ch. 19 - Hypomorphic alleles of a pleiotropic gene...Ch. 19 - In addition to the maternal effect genes that...Ch. 19 - The yan gene encodes a transcription factor that...Ch. 19 - Recall from Chapter 17 that in Drosophila, sex...Ch. 19 - a. Explain the difference between maternal...Ch. 19 - In the 1920s, Arthur Boycott, working with the...Ch. 19 - The Drosophila mutant screen shown on the...Ch. 19 - Some genes are required both zygotically and...Ch. 19 - How would a human with a mutation in a maternal...Ch. 19 - One important demonstration that Bicoid is an...Ch. 19 - The hunchback gene contains a 5 transcriptional...Ch. 19 - In flies developing from eggs laid by a...Ch. 19 - Wild-type embryos and mutant embryos lacking the...Ch. 19 - The Drosophila even-skipped eve gene has four...Ch. 19 - In Drosophila with loss-of-function mutations...Ch. 19 - It is crucial to the development of Drosophila...Ch. 19 - In the plant Arabidopsis thaliana, every flower is...
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