CAMPBEL BIOLOGY:CONCEPTS & CONNECTIONS
10th Edition
ISBN: 9780136538820
Author: Taylor
Publisher: INTER PEAR
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Textbook Question
Chapter 13, Problem 8TYK
Within a few weeks of treatment with the drug 3TC, a patient’s HIV population consists entirely of 3TC-resistant viruses. How can this result best be explained?
a. HIV can change its surface proteins and resist vaccines.
b. The patient must have become reinfected with a resistant virus.
c. A few drug-resistant viruses were present at the start of treatment, and natural selection increased their frequency.
d. HIV began making drug-resistant versions of its enzymes in response to the drug.
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Chapter 13 Solutions
CAMPBEL BIOLOGY:CONCEPTS & CONNECTIONS
Ch. 13 - Summarize the key points of Darwins theory of...Ch. 13 - Complete this concept map describing potential...Ch. 13 - Which of the following did not influence Darwin as...Ch. 13 - Natural selection is sometimes described as...Ch. 13 - In an area of erratic rainfall, a biologist found...Ch. 13 - If an allele is recessive and lethal in...Ch. 13 - In a population with two alleles, B and b, the...Ch. 13 - Within a few weeks of treatment with the drug 3TC,...Ch. 13 - In the late 1700s, machines that could blast...Ch. 13 - Write a paragraph briefly describing the kinds of...
Ch. 13 - In the early 1800s, French naturalist Jean...Ch. 13 - Sickle-cell disease is caused by a recessive...Ch. 13 - It seems logical that natural selection would work...Ch. 13 - SCIENTIFIC THINKING Cetaceans are fully aquatic...Ch. 13 - A population of snails is preyed on by birds that...Ch. 13 - Advocates of scientific creationism and...
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