Question 1

The only mechanism of evolutionary change that is not influenced by chance events is ________.

Accepted Answer

The answer of The only mechanism of evolutionary change that...

Question 2

Disruptive selection operates whenever

Accepted Answer

A) natural selection is disrupted by genetic drift. 
B) there is a balanced gene pool. 
C) only the smallest individuals survive. 
D) both extremes of the phenotype are more successful. 
A) natural selection is disrupted by genetic drift. 
B) there is a balanced gene pool. 
C) only the smallest individuals survive. 
D) both extremes of the phenotype are more successful.

Question 3

In natural selection, ________ that increase survival and reproductive success become more common in a population.

Accepted Answer

A) genotypes 
B) allele frequencies 
C) bottlenecks 
D) phenotypes 
A) genotypes 
B) allele frequencies 
C) bottlenecks 
D) phenotypes

Question 4

UV light causes mutations within skin cells. Is UV light a major driving force in the evolution of animals?

Accepted Answer

A) Yes. UV light is always present outside and can produce both favorable and harmful mutations in skin cells. Only the favorable mutations will be passed on to the next generation. 
B) Yes. A mutation in the skin cell will result in an organism that is better protected from the sun. This individual will be more likely to survive and pass on this mutation to the next generation. 
C) No. Only mutations in gametes will be passed on to the next generation. Only mutations that are passed on to offspring contribute to evolution. 
D) No. Only mutations that have a favorable adaptive quality will be passed on to the next generation. UV light produces only harmful mutations. 
A) Yes. UV light is always present outside and can produce both favorable and harmful mutations in skin cells. Only the favorable mutations will be passed on to the next generation. 
B) Yes. A mutation in the skin cell will result in an organism that is better protected from the sun. This individual will be more likely to survive and pass on this mutation to the next generation. 
C) No. Only mutations in gametes will be passed on to the next generation. Only mutations that are passed on to offspring contribute to evolution. 
D) No. Only mutations that have a favorable adaptive quality will be passed on to the next generation. UV light produces only harmful mutations.

Question 5

Insecticides are used to kill insects. However, insecticide resistant insects are being found. What is the mechanism for this new insect trait?

Accepted Answer

A) An insect with a random mutation is not killed by the insecticide and reproduces. 
B) Exposing insects to insecticides leads to mutations, which make the insects resistant. 
C) Human interference with natural processes leads to genetic drift, which results in resistant insects. 
D) Insecticides kill all the insects in a population, and a different species of resistant insects colonizes the available resources. 
A) An insect with a random mutation is not killed by the insecticide and reproduces. 
B) Exposing insects to insecticides leads to mutations, which make the insects resistant. 
C) Human interference with natural processes leads to genetic drift, which results in resistant insects. 
D) Insecticides kill all the insects in a population, and a different species of resistant insects colonizes the available resources.

Question 6

The following image is an example of

Accepted Answer

A) gene flow. 
B) genetic drift. 
C) natural selection. 
D) mutation. 
A) gene flow. 
B) genetic drift. 
C) natural selection. 
D) mutation.

Question 7

What is genetic drift?

Accepted Answer

A) gene mutation within, or between, populations 
B) chance evolutionary change occurring in small populations 
C) natural selection acting on large populations 
D) shifts in allelic frequencies due to mutation 
A) gene mutation within, or between, populations 
B) chance evolutionary change occurring in small populations 
C) natural selection acting on large populations 
D) shifts in allelic frequencies due to mutation

Question 8

The color of a certain species of beetle is determined by a single gene. Two beetles homozygous for green coloration (meaning they have two copies of the green allele) produce a single offspring with brown coloration. Brown color appeared in this offspring as a result of

Accepted Answer

A) bottleneck. 
B) gene flow. 
C) genetic drift. 
D) mutation. 
A) bottleneck. 
B) gene flow. 
C) genetic drift. 
D) mutation.

Question 9

The original source of genetic variation within a population is ________.

Accepted Answer

The answer of The original source of genetic variation within...

Question 10

How do natural selection and sexual selection differ?

Accepted Answer

A) Natural selection increases the frequency of alleles that contribute to survival, but sexual selection may increase the frequency of alleles that are not beneficial to survival. 
B) Natural selection contributes to genetic drift, but sexual selection contributes to gene flow. 
C) Natural selection is more random than sexual selection. 
D) Natural selection increases the fitness of an allele, but sexual selection increases the dimorphism of an allele. 
A) Natural selection increases the frequency of alleles that contribute to survival, but sexual selection may increase the frequency of alleles that are not beneficial to survival. 
B) Natural selection contributes to genetic drift, but sexual selection contributes to gene flow. 
C) Natural selection is more random than sexual selection. 
D) Natural selection increases the fitness of an allele, but sexual selection increases the dimorphism of an allele.

Question 11

While on a camping trip, you collect a white tadpole from a pond and take it home. The tadpole develops into a white bullfrog. When the frog gets too big, you release it into a local pond. The next year, several white bullfrogs are observed in the pond. This is an example of

Accepted Answer

A) genetic drift. 
B) natural selection. 
C) gene flow. 
D) sexual selection. 
A) genetic drift. 
B) natural selection. 
C) gene flow. 
D) sexual selection.

Question 12

A mutation in a gene produces the identical protein to the original gene and therefore, an identical trait. Will evolution act upon this mutation?

Accepted Answer

A) No, because evolution acts upon phenotypes. 
B) Yes, because evolution acts upon phenotypes. 
C) Yes, because mutations do contribute to evolution 
D) No, because mutations do not contribute to evolution. 
A) No, because evolution acts upon phenotypes. 
B) Yes, because evolution acts upon phenotypes. 
C) Yes, because mutations do contribute to evolution 
D) No, because mutations do not contribute to evolution.

Question 13

The wings of a bird and the wings of a bat both form from the front appendages (arms). The bird wing is covered by feathers, and the bat wing consists of a thin layer of skin stretched between the "finger" bones. Are the wings of the bird and bat homologous or analogous?

Accepted Answer

A) homologous, because they evolved from the same body part 
B) analogous, because birds' flight requires feathers and bats use skin; both are wings, but they evolved differently 
C) both; they are homologous because they both evolved from a front appendage, but analogous because they evolved differently 
D) neither, because birds and bats do not share a recent common ancestor 
A) homologous, because they evolved from the same body part 
B) analogous, because birds' flight requires feathers and bats use skin; both are wings, but they evolved differently 
C) both; they are homologous because they both evolved from a front appendage, but analogous because they evolved differently 
D) neither, because birds and bats do not share a recent common ancestor

Question 14

New world vultures are related to raptors, while old world vultures are more closely related to storks. However, both of these birds eat carrion (decaying animals) and have a similar beak structure. Explain how this similarity in beak structures arose.

Accepted Answer

This is an example of converge

Question 15

Jean-Baptiste Lamark proposed that populations evolve when traits acquired during the lifetime of a parent are passed down to offspring. What is wrong with this proposal?

Accepted Answer

A) Only changes in the DNA sequence of an organism can be inherited. Traits acquired throughout life generally do not involve DNA. 
B) The environment chooses which traits are necessary for survival rather than the individual. 
C) Changes in a species occur at the individual level rather than at the population level. 
D) The inheritance of acquired traits would not lead to speciation because it would cause all of the individuals in a population to become more similar. 
A) Only changes in the DNA sequence of an organism can be inherited. Traits acquired throughout life generally do not involve DNA. 
B) The environment chooses which traits are necessary for survival rather than the individual. 
C) Changes in a species occur at the individual level rather than at the population level. 
D) The inheritance of acquired traits would not lead to speciation because it would cause all of the individuals in a population to become more similar.

Question 16

Both mammals and octopi have evolved similar eye structures. This is an example of

Accepted Answer

A) convergent evolution. 
B) divergent evolution. 
C) disruptive selection. 
D) directional selection. 
A) convergent evolution. 
B) divergent evolution. 
C) disruptive selection. 
D) directional selection.

Question 17

An example of evolution that has been readily observed is

Accepted Answer

A) a chameleon changing colors as it moves from a leaf of one color to a leaf of another color. 
B) increased resistance of bacteria to an antibiotic that is used to kill them. 
C) chimpanzees learning sign language. 
D) humans teaching dogs to obey certain commands. 
A) a chameleon changing colors as it moves from a leaf of one color to a leaf of another color. 
B) increased resistance of bacteria to an antibiotic that is used to kill them. 
C) chimpanzees learning sign language. 
D) humans teaching dogs to obey certain commands.

Question 18

If a given population has 30 RR individuals, 10 Rr individuals, and 10 rr individuals, what is the allele frequency of R?

Accepted Answer

A) 0.1 
B) 0.3 
C) 0.5 
D) 0.7 
A) 0.1 
B) 0.3 
C) 0.5 
D) 0.7

Question 19

A friend states, "Exposing bacteria to antibiotics causes the cells to mutate to become antibiotic resistant." Explain to your friend why he is incorrect and provide the correct explanation.

Accepted Answer

This statement is false. Mutations occur

Question 20

Which of the following is NOT a step in the evolutionary process?

Accepted Answer

A) Mutation results in the formation of new alleles, and sexual reproduction results in new combinations of alleles. 
B) New genes are introduced into a population when members of that population mate with members of other species and produce offspring. 
C) Genetic variation is inherited by the next generation of a population. 
D) Genetic drift, gene flow, and/or natural selection cause allele frequencies to change over time. 
A) Mutation results in the formation of new alleles, and sexual reproduction results in new combinations of alleles. 
B) New genes are introduced into a population when members of that population mate with members of other species and produce offspring. 
C) Genetic variation is inherited by the next generation of a population. 
D) Genetic drift, gene flow, and/or natural selection cause allele frequencies to change over time.

Exam 11: Mechanisms of Evolution

The only mechanism of evolutionary change that is not influenced by chance events is ________.

Disruptive selection operates whenever

In natural selection, ________ that increase survival and reproductive success become more common in a population.

UV light causes mutations within skin cells. Is UV light a major driving force in the evolution of animals?

Insecticides are used to kill insects. However, insecticide resistant insects are being found. What is the mechanism for this new insect trait?

The following image is an example of

What is genetic drift?

The color of a certain species of beetle is determined by a single gene. Two beetles homozygous for green coloration (meaning they have two copies of the green allele) produce a single offspring with brown coloration. Brown color appeared in this offspring as a result of

The original source of genetic variation within a population is ________.

How do natural selection and sexual selection differ?

While on a camping trip, you collect a white tadpole from a pond and take it home. The tadpole develops into a white bullfrog. When the frog gets too big, you release it into a local pond. The next year, several white bullfrogs are observed in the pond. This is an example of

A mutation in a gene produces the identical protein to the original gene and therefore, an identical trait. Will evolution act upon this mutation?

The wings of a bird and the wings of a bat both form from the front appendages (arms). The bird wing is covered by feathers, and the bat wing consists of a thin layer of skin stretched between the "finger" bones. Are the wings of the bird and bat homologous or analogous?

New world vultures are related to raptors, while old world vultures are more closely related to storks. However, both of these birds eat carrion (decaying animals) and have a similar beak structure. Explain how this similarity in beak structures arose.

Jean-Baptiste Lamark proposed that populations evolve when traits acquired during the lifetime of a parent are passed down to offspring. What is wrong with this proposal?

Both mammals and octopi have evolved similar eye structures. This is an example of

An example of evolution that has been readily observed is

If a given population has 30 RR individuals, 10 Rr individuals, and 10 rr individuals, what is the allele frequency of R?

A friend states, "Exposing bacteria to antibiotics causes the cells to mutate to become antibiotic resistant." Explain to your friend why he is incorrect and provide the correct explanation.

Which of the following is NOT a step in the evolutionary process?

The Nature of Science

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Life Is Cellular

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Patterns of Inheritance

Chromosomes and Human Genetics

What Genes Are

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Evidence for Evolution

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The History of Life

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General Principles of Ecology

Growth of Populations

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