Question 1

All the members of a single species that occupy a particular area at the same time are known as a

Accepted Answer

A)   subspecies.
B)   gene pool.
C)   population.
D)   group.
E)   sub-population.F) C) and D)
G) None of the above

Question 2

Another student proposes that handedness could just as easily be passed to children by how the parents carry the child and interact with it, a learning process that may perpetuate from the parents' handedness. Assuming all parents and children are expressing their "true handedness," the occurrence of which case below would cast the most serious doubt on a simple genetic basis for handedness, with left-handedness recessive?

Accepted Answer

A)   Two right-handed parents have a left-handed child.
B)   Two left-handed parents have a right-handed child.
C)   Left-handed parents only have left-handed children.
D)   Right-handed parents only have right-handed children.
E)   None of the choices are correct.F) All of the above
G) B) and C)

Question 3

What is the relative biological fitness of an individual who is heterozygous for sickle-cell disease who lives in Central Illinois vs. an individual who is heterozygous and lives in South Africa?

Accepted Answer

The relative biological fitness of the i...

Question 4

If the mutation rate of individual genes is taken to be about one in 100,000 genes per cell cycle across many organisms, we might expect evolution to proceed at a consistent rate for various forms of life. Which factor could make the accumulation of gene mutations faster or slower among different organisms?

Accepted Answer

A)   Organisms with more genes will likely have more mutations per generation.
B)   More selection of mutations can occur in a shorter period of time for bacteria that replicate each twenty minutes than for humans with a (roughly)  20-year generation span.
C)   Organisms vary in the proportion of DNA that is active and in the percent of loci that have multiple alleles.
D)   All of the choices are correct.E) B) and D)
F) B) and C)

Question 5

If early Viking explorers in Greenland and North America had survived and become the main ancestors of early North American settlers, rather than the mixture of immigrants from across Europe and other continents, today there would be a much higher incidence of Nordic traits in the U.S. population. Such a scenario would demonstrate

Accepted Answer

A)   gene flow from continent to continent.
B)   the bottleneck effect.
C)   genetic drift among the original Viking explorers.
D)   directional selection.
E)   the Founder Effect.F) A) and C)
G) C) and D)

Question 6

Variations within a population are maintained by

Accepted Answer

A)   mutation.
B)   genetic recombination due to fertilization.
C)   gene flow.
D)   All of the choices are correct.E) A) and B)
F) A) and C)

Question 7

The black bellied seed cracker, Pyrenestes, is a West African finch. Within the same geographic region, two subspecies of the finch are found. One subspecies has a large beak, which is efficient at cracking the hard seeds of the sedge, Scleria verrucosa. The other subspecies has a small beak, which is more efficient at eating the soft seeds of the sedge, Scleria goossensii. What type of selection occurred to produce this situation? Explain what a population distribution graph would look like that would depict this type of selection.

Accepted Answer

This is an example of disruptive selecti...

Question 8

Which of the following examples will help maintain diversity within a population?

Accepted Answer

A)   lack of mutations within the population
B)   random mating
C)   absence of migration
D)   natural selectionE) B) and D)
F) All of the above

Question 9

The difference in temperature preference between two populations of Daphnia water fleas is due to a mutation. The original population prefers temperatures near 20 $\degree$C, while the mutant population prefers temperatures between 25 $\degree$C and 30 $\degree$C. Predict how natural selection might affect the geographical distribution of these two populations.

Accepted Answer

Answers may vary. These populations pref...

Question 10

If the Hardy-Weinberg equilibrium is met, what is the net effect?

Accepted Answer

A)   evolution leading to a population better adapted to an unchanging environment
B)   evolution leading to a population better adapted to a changing environment
C)   very slow and continuous evolution with no increased adaptation
D)   no evolution because the alleles in the population remain the sameE) B) and D)
F) A) and B)

Question 11

The Hardy-Weinberg equilibrium is usually met in populations in changing environments.

Accepted Answer

A) True 
 B)False

Question 12

An allele becomes the most common allele in a population by becoming the dominant allele.

Accepted Answer

A) True 
 B)False

Question 13

British land snails are an example of disruptive selection. In the grassy fields, the light-banded snails escape bird predators. In the darker forest, the dark snails survive and the light-banded snails are eaten. The different colored snails have the opportunity to interact and breed across the British landscape. Why doesn't this "disruptive selection" eventually lead to two separate species?

Accepted Answer

A)   There is no reproductive isolation to prevent gene flow.
B)   They are already two separate species, and the intermediate forms are hybrids.
C)   The color forms are probably not genetically determined.
D)   There must be some unknown factor producing an equal stabilizing selection "to hold the species together."
E)   This will result in the formation of two species if given long enough time.F) A) and B)
G) C) and D)

Question 14

Gene mutation occurs at any time, without respect to the mutation's adaptive value or benefit to the organism.

Accepted Answer

A) True 
 B)False

Question 15

Define and give an example of assortative mating. Will this affect genotype frequencies? If so, predict how genotype frequencies will be affected in a population if assortative mating persists.

Accepted Answer

Answers may vary. Assortative mating is ...

Question 16

A population of organisms that reproduce asexually without gametes from other individuals will display more variation than a population that reproduces sexually. This results in a greater likelihood of the population evolving.

Accepted Answer

A) True 
 B)False

Question 17

Which of these conditions is NOT among the requirements of the Hardy-Weinberg equilibrium of allele frequencies in a population?

Accepted Answer

A)   small population with genetic drift
B)   no net migration of alleles into or out of the population
C)   no net mutations
D)   no selection of one genotype over another
E)   random mating populationF) C) and D)
G) A) and C)

Question 18

Which of the following would change the allele frequencies of a population?

Accepted Answer

A)   DNA is stable from generation to generation and does not change, so allele frequencies do not change.
B)   Tall people in a population preferentially marry other tall people and do not marry people who are short or average height.
C)   A population on an island remains isolated and no one leaves or moves onto the island.
D)   All of the answer choices would change allele frequencies of a population.E) B) and C)
F) C) and D)

Question 19

Mutations that result in resistance to specific antibiotics in bacterial organisms occur

Accepted Answer

A)   only when the bacteria are exposed to the drug to which they become resistant.
B)   more often when the bacteria are exposed to the drug.
C)   at any time, even when the bacteria are not exposed to the drug.
D)   only when the bacteria are exposed to radiation or other mutagens.E) B) and D)
F) All of the above

Question 20

Which of the following is true about genetic drift?

Accepted Answer

A)   It is more likely to occur in a large population than in a small population.
B)   It may lead to an allele's becoming fixed in a population when its alternative allele is lost from the population.
C)   It increases the number of heterozygotes in a population.
D)   It increases the frequency of rare alleles in a population.E) A) and D)
F) B) and D)

Exam 16: How Populations Evolve

Correct Answer
verified
This is an example of disruptive selecti...
View Answer

Variations within a population are maintained by

Correct Answer
verified

An allele becomes the most common allele in a population by becoming the dominant allele.

Correct Answer
verified

Which of these conditions is NOT among the requirements of the Hardy-Weinberg equilibrium of allele frequencies in a population?

Correct Answer
verified

Define and give an example of assortative mating. Will this affect genotype frequencies? If so, predict how genotype frequencies will be affected in a population if assortative mating persists.

Correct Answer
verified
Answers may vary. Assortative mating is ...
View Answer

Which of the following is true about genetic drift?

Correct Answer
verified

A population of organisms that reproduce asexually without gametes from other individuals will display more variation than a population that reproduces sexually. This results in a greater likelihood of the population evolving.

Correct Answer
verified

Correct Answer
verified
Answers may vary. These populations pref...
View Answer

Correct Answer
verified

If the Hardy-Weinberg equilibrium is met, what is the net effect?

Correct Answer
verified

Gene mutation occurs at any time, without respect to the mutation's adaptive value or benefit to the organism.

Correct Answer
verified

Correct Answer
verified

What is the relative biological fitness of an individual who is heterozygous for sickle-cell disease who lives in Central Illinois vs. an individual who is heterozygous and lives in South Africa?

Correct Answer
verified
The relative biological fitness of the i...
View Answer

Correct Answer
verified

All the members of a single species that occupy a particular area at the same time are known as a

Correct Answer
verified

The Hardy-Weinberg equilibrium is usually met in populations in changing environments.

Correct Answer
verified

Correct Answer
verified

Mutations that result in resistance to specific antibiotics in bacterial organisms occur

Correct Answer
verified

Which of the following examples will help maintain diversity within a population?

Correct Answer
verified

Which of the following would change the allele frequencies of a population?

Correct Answer
verified

Exam 16: How Populations Evolve

Correct AnswerverifiedThis is an example of disruptive selecti...View AnswerShow Answer

Variations within a population are maintained by

Correct AnswerverifiedShow Answer

An allele becomes the most common allele in a population by becoming the dominant allele.

Correct AnswerverifiedShow Answer

Which of these conditions is NOT among the requirements of the Hardy-Weinberg equilibrium of allele frequencies in a population?

Correct AnswerverifiedShow Answer

Define and give an example of assortative mating. Will this affect genotype frequencies? If so, predict how genotype frequencies will be affected in a population if assortative mating persists.

Correct AnswerverifiedAnswers may vary. Assortative mating is ...View AnswerShow Answer

Which of the following is true about genetic drift?

Correct AnswerverifiedShow Answer

A population of organisms that reproduce asexually without gametes from other individuals will display more variation than a population that reproduces sexually. This results in a greater likelihood of the population evolving.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedAnswers may vary. These populations pref...View AnswerShow Answer

Correct AnswerverifiedShow Answer

If the Hardy-Weinberg equilibrium is met, what is the net effect?

Correct AnswerverifiedShow Answer

Gene mutation occurs at any time, without respect to the mutation's adaptive value or benefit to the organism.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

What is the relative biological fitness of an individual who is heterozygous for sickle-cell disease who lives in Central Illinois vs. an individual who is heterozygous and lives in South Africa?

Correct AnswerverifiedThe relative biological fitness of the i...View AnswerShow Answer

Correct AnswerverifiedShow Answer

All the members of a single species that occupy a particular area at the same time are known as a

Correct AnswerverifiedShow Answer

The Hardy-Weinberg equilibrium is usually met in populations in changing environments.

Correct AnswerverifiedShow Answer

Correct AnswerverifiedShow Answer

Mutations that result in resistance to specific antibiotics in bacterial organisms occur

Correct AnswerverifiedShow Answer

Which of the following examples will help maintain diversity within a population?

Correct AnswerverifiedShow Answer

Which of the following would change the allele frequencies of a population?

Correct AnswerverifiedShow Answer

Correct Answer
verified
This is an example of disruptive selecti...
View Answer

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Answers may vary. Assortative mating is ...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
Answers may vary. These populations pref...
View Answer

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified

Correct Answer
verified
The relative biological fitness of the i...
View Answer

Correct Answer
verified

Correct Answer
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Correct Answer
verified

Correct Answer
verified

Correct Answer
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Correct Answer
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Correct Answer
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