Question 1

For a particular character, natural selection can favor an average phenotype or extreme phenotypes. In order to do this, a character must be:

Accepted Answer

A)  under the control of many genes. 
B)  under the control of only two alleles for a gene. 
C)  not under the control of any genes. 
D)  controlled by a dominant allele for a gene. 
A)  under the control of many genes. 
B)  under the control of only two alleles for a gene. 
C)  not under the control of any genes. 
D)  controlled by a dominant allele for a gene. A

Question 2

Which of the following is incorrectly paired?

Accepted Answer

A)  gene flow: genes move from one population to another 
B)  bottleneck effect: changes in allele frequencies due to chance events 
C)  founder effect: only a small portion of an original population's gene pool are represented 
D)  sexual selection: mating based on phenotype 
A)  gene flow: genes move from one population to another 
B)  bottleneck effect: changes in allele frequencies due to chance events 
C)  founder effect: only a small portion of an original population's gene pool are represented 
D)  sexual selection: mating based on phenotype B

Question 3

Refer to the scenario below, and then answer the following question(s).
Two European men and two Polynesian women settled on a previously uninhabited tropical island. All four of the settlers have brown eyes, a dominant trait, but one of the Europeans is heterozygous and carries the recessive gene for blue eyes.
-After several generations, 35 percent of the island population is found to have AB+ blood. This is much higher than the percentage of AB+ people in the populations from which the original settlers came. The high percentage of AB+ blood is probably due to:

Accepted Answer

A)  founder effect. 
B)  selective mutation. 
C)  disruptive selection. 
D)  nonrandom mating. 
A)  founder effect. 
B)  selective mutation. 
C)  disruptive selection. 
D)  nonrandom mating. A

Question 4

Which of the following males in a given population would be considered the most fit in an evolutionary sense?

Accepted Answer

A)  one that produced 1,000 offspring, of which 100 survived but 99 did not reproduce 
B)  one that produced 100 offspring, of which 10 survived but 9 did not reproduce 
C)  one that produced 1,000 offspring, all of which died before reaching reproductive age 
D)  one that produced two offspring, both of which survived and produced offspring of their own 
A)  one that produced 1,000 offspring, of which 100 survived but 99 did not reproduce 
B)  one that produced 100 offspring, of which 10 survived but 9 did not reproduce 
C)  one that produced 1,000 offspring, all of which died before reaching reproductive age 
D)  one that produced two offspring, both of which survived and produced offspring of their own

Question 5

Extreme hunting pressure has caused northern elephant seals to become less genetically diverse because of:

Accepted Answer

A)  genetic drift. 
B)  population bottleneck. 
C)  natural selection. 
D)  founder effect. 
A)  genetic drift. 
B)  population bottleneck. 
C)  natural selection. 
D)  founder effect.

Question 6

Which of the following is most likely to cause genetic changes in a population that make it better adapted to its environment?

Accepted Answer

A)  nonrandom mating 
B)  natural selection 
C)  gene flow 
D)  genetic drift 
A)  nonrandom mating 
B)  natural selection 
C)  gene flow 
D)  genetic drift

Question 7

Which of the following possibilities is the best indicator of an organism's evolutionary fitness?

Accepted Answer

A)  the number of eggs it produces over its lifetime 
B)  the number of gametes it produces during the years when it is likely to be reproducing 
C)  the number of offspring it produces over its lifetime that survive to breed. 
D)  the number of offspring it produces over its lifetime 
A)  the number of eggs it produces over its lifetime 
B)  the number of gametes it produces during the years when it is likely to be reproducing 
C)  the number of offspring it produces over its lifetime that survive to breed. 
D)  the number of offspring it produces over its lifetime

Question 8

In ________ selection, individuals with an intermediate phenotype are favored over other individuals in the population.

Accepted Answer

The answer of In ________ selection, individuals with an intermediate...

Question 9

Genetic drift occurs when:

Accepted Answer

A)  chance occurrences alter gene frequencies. 
B)  reproduction is nonrandom within the population. 
C)  gene flow within the population is less than gene flow between populations. 
D)  the population has not yet stabilized. 
A)  chance occurrences alter gene frequencies. 
B)  reproduction is nonrandom within the population. 
C)  gene flow within the population is less than gene flow between populations. 
D)  the population has not yet stabilized.

Question 10

How successful an individual is at passing on its genes to the next generation is known as:

Accepted Answer

A)  microevolution. 
B)  adaptation. 
C)  fitness. 
D)  sexual selection. 
A)  microevolution. 
B)  adaptation. 
C)  fitness. 
D)  sexual selection.

Question 11

The most immediate effect of sexual displays and contests in animals (such as bighorn sheep bashing their heads together) is:

Accepted Answer

A)  mutations. 
B)  differential mating success. 
C)  disruptive selection. 
D)  stabilizing selection. 
A)  mutations. 
B)  differential mating success. 
C)  disruptive selection. 
D)  stabilizing selection.

Question 12

Two nearby populations in which there is some movement of individuals between the populations are an example of:

Accepted Answer

A)  disruptive selection. 
B)  bottleneck effect. 
C)  genetic drift. 
D)  gene flow. 
A)  disruptive selection. 
B)  bottleneck effect. 
C)  genetic drift. 
D)  gene flow.

Question 13

African black-bellied seedcracker finches have beaks that are either large or small. Only large-beaked birds can crack open hard seeds, and small-beaked birds are more adept at handling small seeds. Both have an advantage over intermediate-sized beaks. This is an example of a response to:

Accepted Answer

A)  directional selection. 
B)  stabilizing selection. 
C)  disruptive selection. 
D)  sexual selection. 
A)  directional selection. 
B)  stabilizing selection. 
C)  disruptive selection. 
D)  sexual selection.

Question 14

The most important kind of selection acting on a well-adapted population in a relatively constant environment is:

Accepted Answer

A)  disruptive. 
B)  stabilizing. 
C)  directional. 
D)  catastrophic. 
A)  disruptive. 
B)  stabilizing. 
C)  directional. 
D)  catastrophic.

Question 15

________ is necessary for a population to survive over successive generations in response to environmental changes.

Accepted Answer

A)  Adaptation 
B)  Sexual selection 
C)  Speciation 
D)  Gene flow 
A)  Adaptation 
B)  Sexual selection 
C)  Speciation 
D)  Gene flow

Question 16

Which of the following statements is true?

Accepted Answer

A)  The advantage a trait conveys depends on its environmental context. 
B)  A population will always evolve to fit current conditions. 
C)  All traits are simultaneously maximized in a population. 
D)  All traits currently in a population must have provided a reproductive advantage at some point in time. 
A)  The advantage a trait conveys depends on its environmental context. 
B)  A population will always evolve to fit current conditions. 
C)  All traits are simultaneously maximized in a population. 
D)  All traits currently in a population must have provided a reproductive advantage at some point in time.

Question 17

The formation of new species over many generations is an example of:

Accepted Answer

A)  microevolution. 
B)  macroevolution. 
C)  gene pools. 
D)  allelic variants. 
A)  microevolution. 
B)  macroevolution. 
C)  gene pools. 
D)  allelic variants.

Question 18

What is the difference between microevolution and macroevolution?

Accepted Answer

A)  Microevolution is hypothetical because changes are too small to be observed, whereas macroevolution is detectable. 
B)  Microevolution deals with microscopic organisms, whereas macroevolution deals with larger ones. 
C)  Microevolution describes what happens in small populations, whereas macroevolution deals with large populations. 
D)  Microevolution describes changes within a population over a short period of time, whereas macroevolution describes larger changes such as the formation of new species over longer periods of time. 
A)  Microevolution is hypothetical because changes are too small to be observed, whereas macroevolution is detectable. 
B)  Microevolution deals with microscopic organisms, whereas macroevolution deals with larger ones. 
C)  Microevolution describes what happens in small populations, whereas macroevolution deals with large populations. 
D)  Microevolution describes changes within a population over a short period of time, whereas macroevolution describes larger changes such as the formation of new species over longer periods of time.

Question 19

The concept of evolution has always been connected with some notion of progress-natural selection pushing populations toward better and better adaptations to create "perfect organisms." How would you argue that evolution does not craft perfect organisms?

Accepted Answer

Natural selection adapts populations to

Question 20

Disruptive selection operates whenever:

Accepted Answer

A)  a phenotype is more successful because it is rare. 
B)  natural selection is disrupted by genetic drift. 
C)  the extremes in a distribution of phenotypes are more fit than the average. 
D)  only the largest individuals survive. 
A)  a phenotype is more successful because it is rare. 
B)  natural selection is disrupted by genetic drift. 
C)  the extremes in a distribution of phenotypes are more fit than the average. 
D)  only the largest individuals survive.

Exam 17: The Means of Evolution: Microevolution

For a particular character, natural selection can favor an average phenotype or extreme phenotypes. In order to do this, a character must be:

Which of the following is incorrectly paired?

Which of the following males in a given population would be considered the most fit in an evolutionary sense?

Extreme hunting pressure has caused northern elephant seals to become less genetically diverse because of:

Which of the following is most likely to cause genetic changes in a population that make it better adapted to its environment?

Which of the following possibilities is the best indicator of an organism's evolutionary fitness?

In ________ selection, individuals with an intermediate phenotype are favored over other individuals in the population.

Genetic drift occurs when:

How successful an individual is at passing on its genes to the next generation is known as:

The most immediate effect of sexual displays and contests in animals (such as bighorn sheep bashing their heads together) is:

Two nearby populations in which there is some movement of individuals between the populations are an example of:

African black-bellied seedcracker finches have beaks that are either large or small. Only large-beaked birds can crack open hard seeds, and small-beaked birds are more adept at handling small seeds. Both have an advantage over intermediate-sized beaks. This is an example of a response to:

The most important kind of selection acting on a well-adapted population in a relatively constant environment is:

________ is necessary for a population to survive over successive generations in response to environmental changes.

Which of the following statements is true?

The formation of new species over many generations is an example of:

What is the difference between microevolution and macroevolution?

The concept of evolution has always been connected with some notion of progress-natural selection pushing populations toward better and better adaptations to create "perfect organisms." How would you argue that evolution does not craft perfect organisms?

Disruptive selection operates whenever:

Science As a Way of Learning: a Guide to the Natural World

Fundamental Building Blocks: Chemistry, Water, and Ph

Lifes Components: Biological Molecules

Lifes Home: the Cell

Lifes Border: the Plasma Membrane

Lifes Mainspring: an Introduction to Energy

Vital Harvest: Deriving Energy From Food

The Green Worlds Gift: Photosynthesis

The Links in Lifes Chain: Genetics and Cell Division

Preparing for Sexual Reproduction: Meiosis

The First Geneticist: Mendel and His Discoveries

Units of Heredity: Chromosomes and Inheritance

Passing on Lifes Information: Dna Structure and Replication

How Proteins Are Made: Genetic Transcription, Translation, and Regulation

The Future Isnt What It Used to Be: Biotechnology

An Introduction to Evolution: Charles Darwin, Evolutionary Thought, and the Evidence for Evolution

The Outcomes of Evolution: Macroevolution

A Slow Unfolding: the History of Life on Earth

Arriving Late, Traveling Far: the Evolution of Human Beings

Viruses, Bacteria, Archaea, and Protists: the Diversity of Life 1

Fungi : the Diversity of Life 2

Animals: the Diversity of Life 3

Plants: the Diversity of Life 4

The Angiosperms: Form and Function in Flowering Plants

Body Support and Movement: the Integumentary, Skeletal, and Muscular Systems

Communication and Control 1: the Nervous System

Communication and Control 2: the Endocrine System

Defending the Body: the Immune System

Transport and Exchange 1: Blood and Breath

Transport and Exchange 2: Digestion, Nutrition, and Elimination

An Amazingly Detailed Script: Animal Development

How the Baby Came to Be: Human Reproduction

An Interactive Living World 1: Populations in Ecology

An Interactive Living World 2: Communities in Ecology

An Interactive Living World 3: Ecosystems and Biomes

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