Campbell Biology: Concepts & Connections (8th Edition)
8th Edition
ISBN: 9780321885326
Author: Jane B. Reece, Martha R. Taylor, Eric J. Simon, Jean L. Dickey, Kelly A. Hogan
Publisher: PEARSON
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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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Which of the following statements accurately describes what we learned about HIV evolution?
a.
HIV is more deadly in Northern Europe, but more transmissible in Africa. That is why there are more individuals infected with the illness in Africa.
b.
HIV shares a most recently common ancestor with Simian Immunodeficiency Virus (SIV) such that SIV evolved as it host-switched from chimpanzees and gorillas into humans multiple times.
c.
Drug development is exceedingly difficult because there are very few drug targets for HIV and AZT (a reverse transcriptase inhibitor) alone is the single most effective treatment for HIV.
d.
Evolution of HIV virions within a person is quite slow such that a blood draw after 1 year of infection would reveal that every single virion would have the exact same sequence.
Why is the Nipah virus a great illustration of a zoonotic disease?
A.
Because it's carried by fruit bats across America but it's not even noticed by the American people.
B.
Because it's carried by cats across Asia and easily spills over into humans.
C.
Because it's carried by fruit bats across Asia but almost never spills over into humans.
D.
Because it's carried by fruit bats across Asia and easily spills over into humans.
Why is the Nipah virus a great illustration of a zoonotic disease?
A. Because it's carried by fruit bats across Asia but almost never spills over into humans.
B. Because it's carried by cats across Asia and easily spills over into humans.
C. Because it's carried by fruit bats across Asia and easily spills over into humans.
D. Because it's carried by fruit bats across America but it's not even noticed by the American people.
Chapter 13 Solutions
Campbell Biology: Concepts & Connections (8th Edition)
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 - Prob. 9TYKCh. 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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- What was “the scariest moment of the Ebola epidemic” and why? A. When it became undetectable - because it had obviously mutated to hide itself. B. When it was found in the U.S. C. When it was found in India - because of the high population density there. D. When it was found in Lagos - a city with the population of three African countries combinedarrow_forwardThe media has recently reported that a high number of patients while staying in the hospital, are gettinginfections caused by antibiotic-resistant bacteria. Using evolutionary theory, explain how this could occur.arrow_forwardHow did the Ebola outbreak start in 2014? A. A two-year old boy handled an infected bat. B. A family ate an infected pig for dinner. C. A four-year old girl was bit by an infected bird. D. A father was bit by a rabid dog.arrow_forward
- According to the endosymbiotic theory, why was it adaptive for the larger (host) cell to keep the engulfed cell alive, rather than digesting it as food? A. The host cell would have been poisoned if it had digested the engulfed cell. B. The host cell was able to survive anaerobic conditions with the engulfed cell alive. C. The engulfed cell provided the host cell with CO2 D. The engulfed cell provided the host cell with ATP. E. The engulfed cell allowed the host cell to metabolize glucose.arrow_forwardUsing the diagram answer the following question.arrow_forwardIn the case of the Ebola outbreak in the Democratic Republic of the Congo (then called Zaire) in 1976, how did the virus first transmit to humans? A. A teacher ate a wild bat B. A teacher ate a wild antelope C. Scientists are still unsure D. A mosquito bit a teacherarrow_forward
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