Biology
12th Edition
ISBN: 9780134813448
Author: Audesirk, Teresa, Gerald, Byers, Bruce E.
Publisher: Pearson,
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Chapter 15.3, Problem 2CSC
What Good Are Wisdom Teeth and Ostrich Wings?
Just as anatomical homology can lead to vestigial structures such as human wisdom teeth and the wings of flightless birds, genetic homology can lead to vestigial DMA sequences. For example, most mammal species produce an enzyme. L-gulonolactone oxidase, that catalyzes the last step in the production of vitamin C. The species that produce the enzyme are able to do so because they all inherited the gene that encodes it from a common ancestor. Humans, however, do not produce L-gulonolactone oxidase, so we can’t produce vitamin C ourselves and must consume it in our diets. But even though we don’t produce the enzyme, our cells do contain a stretch of DMA with a sequence very similar to that of the enzyme-producing gene present in rats and most other mammals. The human version. though, does not encode the enzyme (or any protein). We inherited this stretch of DNA from an ancestor that we share with other mammal species, but in us, the sequence has undergone a change that rendered it nonfunctional. (The change probably did not confer a strong disadvantage, because our ancestors got sufficient vitamin C in their diets.) The nonfunctional sequence remains as a vestigial trait, evidence of our shared ancestry.
Vestigial traits are evidence of both shared ancestry and change in traits over time. What kinds of observations and experiments show that natural selection contributes to evolutionary change?
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Chapter 15 Solutions
Biology
Ch. 15.1 - identify some of the thinkers whose ideas set the...Ch. 15.1 - Prob. 2CYLCh. 15.1 - define evolution?Ch. 15.2 - A recent study found that Galpagos mockingbirds on...Ch. 15.2 - Prob. 2TCCh. 15.2 - explain how natural selection works and how it...Ch. 15.2 - describe the logic, based on four postulates, by...Ch. 15.3 - The fossil history of some kinds of modem...Ch. 15.3 - What Good Are Wisdom Teeth and Ostrich Wings?...Ch. 15.3 - Are a peacocks tail and a dogs tail homologous...
Ch. 15.3 - Between 70% and 85% of people will experience...Ch. 15.3 - describe the evidence that evolution has occurred?Ch. 15.3 - explain the difference between similarity due to...Ch. 15.3 - What Good Are Wisdom Teeth and Ostrich Wings? Just...Ch. 15.4 - To reduce the incidence of pesticide resistance,...Ch. 15.4 - describe some observations and experiments that...Ch. 15.4 - Some advocates of the view that all organisms were...Ch. 15 - Whale skeletons contain nonfunctional pelvic bones...Ch. 15 - Darwin was influenced by Malthuss thinking about...Ch. 15 - Prob. 3MCCh. 15 - Which of the following is not required for...Ch. 15 - Prob. 5MCCh. 15 - The flipper of a seal is homologous with the _____...Ch. 15 - Prob. 2FIBCh. 15 - Georges Cuvier espoused a concept called ______ to...Ch. 15 - Prob. 4FIBCh. 15 - Prob. 5FIBCh. 15 - Darwin's postulate 2 states that ______. The work...Ch. 15 - Prob. 1RQCh. 15 - Distinguish between catastrophism and...Ch. 15 - Describe Lamarcks theory of inheritance of...Ch. 15 - What is natural selection? Describe how natural...Ch. 15 - Describe how evolution occurs. In your...Ch. 15 - What is convergent evolution? Give an example.Ch. 15 - How do biochemistry and molecular genetics...Ch. 15 - In what sense are humans currently acting as...Ch. 15 - In discussions of untapped human potential, It is...Ch. 15 - Does evolution through natural selection produce...
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