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The weakened viruses contained in live-virus vaccines can


A) trigger an immune response.
B) evolve into a new strain of virus.
C) be ineffective at providing immunity.
D) cause the same symptoms as the normal virus.

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Imagine that in the future we discover a set of genes that is largely responsible for causing aging in humans. Also, imagine that we can alter these genes in some way so that we live longer. Considering antagonistic pleiotropy, why might this be a concern?

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Antagonistic pleiotropy is a biological ...

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Sequencing genomes of the Lassa virus to test hypotheses about its spread is an example of the application of


A) evolutionary medicine.
B) medical biology.
C) genetics.
D) phylogenies.

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What does the flu virus use the protein hemagglutinin for?


A) to weaken the membrane of the host cell
B) to aid in copying the flu genome
C) to latch onto acids on the host cell
D) to recruit the host cell's genetic machinery

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Which of the following viruses has/have jumped to humans from another species?


A) HIV
B) SARS
C) influenza
D) all of the above

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After studying the phylogeny of the Lassa virus, scientists discovered that viruses from different regions were not closely related to each other. This supports the hypothesis that


A) the virus was spreading from person to person.
B) the virus jumped from rats to people recently.
C) the virus was jumping repeatedly from rats to people.
D) there were no genetic patterns to the transmission of the virus.

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Understanding how selection affects virulence has led public health officials to use which of the following actions to reduce the transmission of pathogens?


A) providing clean drinking water
B) encouraging hand washing
C) vaccinating a large portion of the population
D) all of the above

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The virulence of a pathogen is not fixed, meaning that


A) pathogens can't evolve to become more virulent.
B) pathogens can evolve to become more or less virulent.
C) all species of pathogens do not have the same virulence.
D) virulence can vary among species but not within a species.

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In the future, an increase in emerging pathogens from animal sources is


A) an inevitable consequences of evolution.
B) likely to decrease as scientists find ways to combat viruses.
C) likely to increase as humans intrude farther into wild regions.
D) not a likely threat because scientists have eliminated viruses like SARS.

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What fraction of the world's population got sick with the flu in 1918?


A) 1/100
B) 1/10
C) 1/3
D) 1/2

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Mutations occur across the genome at random, but tumors form when a mutation occurs in genes that control


A) the production of antibodies.
B) the rate of cell division.
C) the regulation of hormones.
D) the storage of energy.

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The process of creating conditions in which viruses evolve reduced virulence is


A) attenuation.
B) resistance development.
C) serial passage.
D) vaccination.

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Describe how knowing the ancestry and genetic makeup of an individual could help doctors diagnose and treat them.

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Knowing the ancestry and genetic makeup ...

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The argument that susceptibility to diabetes and obesity rose as people adapted to different climates provides an alternative to which idea?


A) antagonistic pleiotropy
B) hygiene hypothesis
C) Old Friends hypothesis
D) thrifty genotype hypothesis

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We take a number of measures to decrease the spread of viruses from one person to another (for example, vaccines). Over time, what effect might these efforts have on the evolution of virulence in pathogens?

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The measures taken to decrease the sprea...

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Which statement best describes antagonistic pleiotropy?


A) Certain diseases have low frequencies in young people, but the frequencies increase as people age.
B) There are many genes that work together to control aging and thus many opportunities for mutations.
C) Some diseases have low frequencies in geographic populations with high frequencies of certain mutations.
D) Mutations contributing to aging can increase in frequency if those same mutations promote fitness earlier in life.

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Considering the evolution of antibiotic resistance, why is it important that patients finish their full cycle of antibiotic treatment?

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It is important for patients to finish t...

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A drug called AZT was the first to be used against HIV. Although it initially worked, resistance developed quickly, and eventually the drug was no longer effective. Drug therapies used today, which often combine several different drugs that target different phases of the HIV life cycle into a cocktail, are much more effective over the long term than a single drug used in isolation. Please provide an evolutionary explanation for why newer therapies work better.

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The evolutionary explanation for why new...

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Explain, from an evolutionary perspective, why diseases such as smallpox and measles had such a devastating impact on populations indigenous to the New World.

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From an evolutionary perspective, diseas...

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Selection within pathogen hosts typically favors ________; selection across hosts favors ________.


A) more virulent strains; less virulent strains
B) less virulent strains; more virulent strains
C) less virulent strains; less virulent strains
D) more virulent strains; more virulent strains

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