Genetics: Analysis and Principles
6th Edition
ISBN: 9781259616020
Author: Robert J. Brooker Professor Dr.
Publisher: McGraw-Hill Education
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Chapter 29, Problem 3EQ
Two diploid species of closely related frogs, which we will call species A and species B, were analyzed with regard to the genes that encode an enzyme called hexokinase. Species A has two distinct copies of this gene: A1 and A2. In other words, this diploid species is A1A1 A2A2. Species B has three copies of the hexokinase gene, which we will call B1, B2, and B3. A diploid individual of species B would be B1B1 B2B2 B3B3. These hexokinase genes from the two species were subjected to DNA sequencing, and the percentage of sequence identity was compared among these genes. The results are shown here.
Percentage of DNA Sequence Identity
| A1 | A2 | B1 | B2 | B3 | |
| A1 | 100 | 62 | 54 | 94 | 53 |
| A2 | 62 | 100 | 91 | 49 | 92 |
| B1 | 54 | 91 | 100 | 67 | 90 |
| B2 | 94 | 49 | 67 | 100 | 64 |
| B3 | 53 | 92 | 90 | 64 | 100 |
If we assume that hexokinase genes were never lost in the evolution of these frog species, how many distinct hexokinase genes do you think there were in the most recent ancestor that preceded the divergence of these two species? Explain your answer. Also explain why species B has three distinct copies of this gene, whereas species A has only two.
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Chapter 29 Solutions
Genetics: Analysis and Principles
Ch. 29.1 - Prob. 1COMQCh. 29.1 - Prob. 2COMQCh. 29.1 - 3. A pair of birds flies to a deserted island and...Ch. 29.1 - Prob. 4COMQCh. 29.2 - 1. Phylogenetic trees are based on
a. natural...Ch. 29.2 - Prob. 2COMQCh. 29.2 - An approach that is used to construct a...Ch. 29.2 - 4. Horizontal gene transfer is a process in which...Ch. 29.3 - Prob. 1COMQCh. 29.3 - Prob. 2COMQ
Ch. 29.3 - When the chromosomes of closely related species...Ch. 29 - 1. Discuss the two principles on which evolution...Ch. 29 - 2. Evolution, which involves genetic changes in a...Ch. 29 - Prob. 3CONQCh. 29 - Prob. 4CONQCh. 29 - 5. Would each of the following examples of...Ch. 29 - Distinguish between anagenesis and cladogenesis....Ch. 29 - 7. Describe three or more genetic mechanisms that...Ch. 29 - Explain the type of speciation (allopatric,...Ch. 29 - Prob. 9CONQCh. 29 - Prob. 10CONQCh. 29 - Discuss the major differences among allopatric,...Ch. 29 - Prob. 12CONQCh. 29 - Prob. 13CONQCh. 29 - Would the rate of deleterious or beneficial...Ch. 29 - 15. Which would you expect to exhibit a faster...Ch. 29 - Prob. 16CONQCh. 29 - 17. Plant seeds contain storage proteins that are...Ch. 29 - Take a look at the -globin and -globin amino acid...Ch. 29 - Compare and contrast the neutral theory of...Ch. 29 - Prob. 20CONQCh. 29 - 21. As discussed in Chapter 27, genetic variation...Ch. 29 - Prob. 22CONQCh. 29 - Two populations of snakes are separated by a...Ch. 29 - 2. Sympatric speciation by allotetraploidy has...Ch. 29 - 3. Two diploid species of closely related frogs,...Ch. 29 - A researcher sequenced a portion of a bacterial...Ch. 29 - F1hybrids between two species of cotton,Gossypium...Ch. 29 - 6. A species of antelope has 20 chromosomes per...Ch. 29 - Prob. 7EQCh. 29 - 8. Prehistoric specimens often contain minute...Ch. 29 - From the results of the experiment of Figure...Ch. 29 - InChapter 23, a technique called fluorescence in...Ch. 29 - Prob. 11EQCh. 29 - 12. Discuss how the principle of parsimony can be...Ch. 29 - 13. A homologous DNA region, which was 20,000 bp...Ch. 29 - Prob. 14EQCh. 29 - Prob. 1QSDCCh. 29 - 2. Compare the forms of speciation that are slow...Ch. 29 - 3. Do you think that Darwin would object to the...
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