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 7, Problem 25P
Albinism in animals is caused by recessive mutations in one of several autosomal genes required for synthesis of melanin, a chemical precursor for many skin and eye pigments. Albino animals are often confused with so-called leucistic animals that are white due to recessive mutations in a gene required in a different pathway, for example a pathway for development of the cells that produce all skin pigments. Suppose you have two white hummingbirds-
a male and female—and they have mated. Assuming that all relevant mutations are rare, autosomal, and recessive to wild-type alleles, what would you expect their progeny to look like under the following conditions:
| a. | They are both albinos. | They are both leucistic. |
| c. | One is albino and the other is leucistic. | |
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Chapter 7 Solutions
Genetics: From Genes to Genomes
Ch. 7 - The following is a list of mutational changes. For...Ch. 7 - What explanations can account for the following...Ch. 7 - The DNA sequence of one strand of a gene from...Ch. 7 - Among mammals, measurements of the rate of...Ch. 7 - Over a period of several years, a large hospital...Ch. 7 - Suppose you wanted to study genes controlling the...Ch. 7 - In a genetics lab, Kim and Maria infected a sample...Ch. 7 - The results of the fluctuation test Fig. 7.5 were...Ch. 7 - The following pedigree shows the inheritance of a...Ch. 7 - Autism is a neurological disorder thought to be...
Ch. 7 - Like the yellow Labrador retrievers featured in...Ch. 7 - Remember that Balancer chromosomes prevent the...Ch. 7 - Figure 7.14 shows examples of base substitutions...Ch. 7 - Figure 7.14a shows the mutagen 5-bromouracil 5-BU,...Ch. 7 - So-called two-way mutagens can induce both a...Ch. 7 - In 1967, J. B. Jenkins treated wild-type male...Ch. 7 - When a particular mutagen identified by the Ames...Ch. 7 - Prob. 18PCh. 7 - The Ames test uses the reversion rate His- to His...Ch. 7 - The mutant FMR-1 allele that causes fragile X...Ch. 7 - The physicist Stephen Hawking, famous for his...Ch. 7 - Aflatoxin B1 is a highly mutagenic and...Ch. 7 - In human DNA, 70 of cytosine residues that are...Ch. 7 - Bromodeoxyuridine BrdU is a synthetic nucleoside...Ch. 7 - Albinism in animals is caused by recessive...Ch. 7 - a. In Figure 7.22b, what can you say about the...Ch. 7 - Imagine that you caught a female albino mouse in...Ch. 7 - Plant breeders studying genes influencing leaf...Ch. 7 - In humans, albinism is normally inherited in an...Ch. 7 - a. Seymour Benzers fine structure analysis of the...Ch. 7 - a. You have a test tube containing 5 ml of a...Ch. 7 - Prob. 32PCh. 7 - The rosy ry gene of Drosophila encodes an enzyme...Ch. 7 - Nine rII- mutants of bacteriophage T4 were used in...Ch. 7 - In a haploid yeast strain, eight recessive...Ch. 7 - In Problem 24, you learned that Bloom syndrome is...Ch. 7 - The pathway for arginine biosynthesis in...Ch. 7 - In corn snakes, the wild-type color is brown. One...Ch. 7 - In a certain species of flowering plants with a...Ch. 7 - The intermediates A, B, C, D, E, and F all occur...Ch. 7 - In each of the following cross schemes, two...Ch. 7 - Prob. 42PCh. 7 - The following complementing E. coli mutants were...Ch. 7 - In 1952, an article in the British Medical Journal...Ch. 7 - Mutations in an autosomal gene in humans cause a...Ch. 7 - Antibodies were made that recognize six proteins...Ch. 7 - Prob. 47PCh. 7 - Prob. 48PCh. 7 - In addition to the predominant adult hemoglobin,...Ch. 7 - Most mammals, including New World primates such as...Ch. 7 - Humans are normally trichromats; we have three...
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