Question 1

Which of the following statements is most consistent with data obtained from the fossil record?

Accepted Answer

A)  Older strata carry fossils that differ greatly from living organisms. 
B)  Geologic changes occur quickly on Earth. 
C)  Unused body parts decrease in size. 
D)  Organisms have an innate drive to increase in complexity. 
A)  Older strata carry fossils that differ greatly from living organisms. 
B)  Geologic changes occur quickly on Earth. 
C)  Unused body parts decrease in size. 
D)  Organisms have an innate drive to increase in complexity. A

Question 2

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by MRSA. How can this best be explained?

Accepted Answer

A)  A patient must have become infected with MRSA from another community. 
B)  In response to the drug, S. aureus began making drug-resistant versions of the protein targeted by the drug. 
C)  Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency. 
D)  S. aureus evolved to resist vaccines. 
A)  A patient must have become infected with MRSA from another community. 
B)  In response to the drug, S. aureus began making drug-resistant versions of the protein targeted by the drug. 
C)  Some drug-resistant bacteria were present at the start of treatment, and natural selection increased their frequency. 
D)  S. aureus evolved to resist vaccines. C

Question 3

Emerald ash borers are beetles whose larvae eat the leaves of ash trees. Without treatment of the trees, the beetles usually kill all ash trees in an area within 10 years. Which of the following events would provide the best possible avenue for saving the ash trees?

Accepted Answer

A)  development of a new pesticide that kills 50% of the emerald ash borers 
B)  constant application of DDT to kill the beetles 
C)  recognition by ash trees of the need for a chemical defense and subsequent production of the chemical by the ash trees to kill the beetles 
D)  discovery of a gene in ash trees that prevents feeding by emerald ash borers and subsequent breeding of more ash trees with this chemical 
A)  development of a new pesticide that kills 50% of the emerald ash borers 
B)  constant application of DDT to kill the beetles 
C)  recognition by ash trees of the need for a chemical defense and subsequent production of the chemical by the ash trees to kill the beetles 
D)  discovery of a gene in ash trees that prevents feeding by emerald ash borers and subsequent breeding of more ash trees with this chemical D

Question 4

In a hypothetical environment, fishes called pike-cichlids locate their prey by sight and eat small, immature algae-eating fish. Thus, the population of algae-eaters experiences predatory pressure from pike-cichlids. Which of the following possible changes is LEAST likely to occur in the algae-eater population in future generations?

Accepted Answer

A)  improved camouflage of the algae-eaters 
B)  decreased day-time activity by algae-eaters 
C)  increased size of female algae-eaters that then produce more and larger young 
D)  production of fewer offspring by algae-eaters 
A)  improved camouflage of the algae-eaters 
B)  decreased day-time activity by algae-eaters 
C)  increased size of female algae-eaters that then produce more and larger young 
D)  production of fewer offspring by algae-eaters

Question 5

Continental drift (plate tectonics) has moved continents around the globe. Which of the following predictions would be most likely?

Accepted Answer

A)  Most species will occur only on one continent. 
B)  No species will occur on all continents. 
C)  The most recently separated continents will have the most closely related species. 
D)  There is not enough information to make a prediction. 
A)  Most species will occur only on one continent. 
B)  No species will occur on all continents. 
C)  The most recently separated continents will have the most closely related species. 
D)  There is not enough information to make a prediction.

Question 6

Which of the following observations helped Darwin shape his concept of descent with modification?

Accepted Answer

A)  Species diversity declines farther from the equator. 
B)  Fewer species live on islands than on the nearest continents. 
C)  Birds live on islands located farther from the mainland than the birds' maximum nonstop flight distance. 
D)  South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe. 
A)  Species diversity declines farther from the equator. 
B)  Fewer species live on islands than on the nearest continents. 
C)  Birds live on islands located farther from the mainland than the birds' maximum nonstop flight distance. 
D)  South American temperate plants are more similar to the tropical plants of South America than to the temperate plants of Europe.

Question 7

The upper forelimbs of humans and bats have fairly similar skeletal structures, whereas the corresponding bones in whales have very different shapes and proportions. However, genetic data suggest that all three kinds of organisms diverged from a common ancestor at about the same time. Which of the following is the most likely explanation for these data?

Accepted Answer

A)  Forelimb evolution was adaptive in people and bats, but not in whales. 
B)  Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. 
C)  Genes mutate faster in whales than in humans or bats. 
D)  Whales are not properly classified as mammals. 
A)  Forelimb evolution was adaptive in people and bats, but not in whales. 
B)  Natural selection in an aquatic environment resulted in significant changes to whale forelimb anatomy. 
C)  Genes mutate faster in whales than in humans or bats. 
D)  Whales are not properly classified as mammals.

Question 8

Which of the following statements best describes the effect of natural selection on a population?

Accepted Answer

A)  improved match between a population and its environment 
B)  increased genetic variation among individuals in a population 
C)  increased mutation rate in the population 
D)  reduction in population size 
A)  improved match between a population and its environment 
B)  increased genetic variation among individuals in a population 
C)  increased mutation rate in the population 
D)  reduction in population size

Question 9

DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Instead, DDT is now largely ineffective against many insects. Which of the following possible actions would have had the best chance of preventing this evolution of DDT resistance?

Accepted Answer

A)  All habitats should have received applications of DDT at about the same time. 
B)  The frequency of DDT application should have been higher. 
C)  The use of DDT should have been interspersed with the use of other pesticides that have a different mode of action. 
D)  DDT application should have been continual. 
A)  All habitats should have received applications of DDT at about the same time. 
B)  The frequency of DDT application should have been higher. 
C)  The use of DDT should have been interspersed with the use of other pesticides that have a different mode of action. 
D)  DDT application should have been continual.

Question 10

Which of the following statements best defines artificial selection?

Accepted Answer

A)  Artificial selection is a process that occurs when individuals inherit traits that enable them to survive and reproduce. 
B)  Artificial selection is a process in which humans decide which plants and/or animals will and will not breed. 
C)  Artificial selection is a process in which humans protect domesticated species from predation. 
D)  Artificial selection is a process that produces beneficial mutations. 
A)  Artificial selection is a process that occurs when individuals inherit traits that enable them to survive and reproduce. 
B)  Artificial selection is a process in which humans decide which plants and/or animals will and will not breed. 
C)  Artificial selection is a process in which humans protect domesticated species from predation. 
D)  Artificial selection is a process that produces beneficial mutations.

Question 11

The diagram is reminiscent of Darwin's sketch showing the branching of evolution. The horizontal axis of the diagram is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular.   Which combination of ideas is represented in the diagram?

Accepted Answer

A)  extinction and mutation 
B)  origin of new species and mutation 
C)  natural selection and overreproduction 
D)  origin of new species and extinction 
A)  extinction and mutation 
B)  origin of new species and mutation 
C)  natural selection and overreproduction 
D)  origin of new species and extinction

Question 12

Which of the following statements about evolutionary trees is accurate?

Accepted Answer

A)  Evolutionary trees are considered evolutionary hypotheses. 
B)  Evolutionary trees are considered evolutionary theories. 
C)  Evolutionary trees are developed when they are confirmed by fossil evidence. 
D)  Evolutionary trees cannot be tested by gathering more evidence. 
A)  Evolutionary trees are considered evolutionary hypotheses. 
B)  Evolutionary trees are considered evolutionary theories. 
C)  Evolutionary trees are developed when they are confirmed by fossil evidence. 
D)  Evolutionary trees cannot be tested by gathering more evidence.

Question 13

Which of the following observations helped Darwin agree with Lyell that Earth was more than a few thousand years old?

Accepted Answer

A)  experiencing an earthquake and seeing fossils of ocean organisms high in the Andes 
B)  experiencing a tidal wave and seeing fossils of ocean organisms in the interior lands of the Galapagos islands 
C)  observing the immigration of new finch species to a bare island in the Galapagos and seeing the development of a new species 
D)  observing the variety of mockingbirds on the different Galapagos Islands as well as understanding that they were most similar to species in South America 
A)  experiencing an earthquake and seeing fossils of ocean organisms high in the Andes 
B)  experiencing a tidal wave and seeing fossils of ocean organisms in the interior lands of the Galapagos islands 
C)  observing the immigration of new finch species to a bare island in the Galapagos and seeing the development of a new species 
D)  observing the variety of mockingbirds on the different Galapagos Islands as well as understanding that they were most similar to species in South America

Question 14

Which of the following is not an observation or inference on which natural selection is based?

Accepted Answer

A)  There is heritable variation among individuals. 
B)  Poorly adapted individuals never produce offspring. 
C)  Species produce more offspring than the environment can support. 
D)  Only a fraction of an individual's offspring may survive. 
A)  There is heritable variation among individuals. 
B)  Poorly adapted individuals never produce offspring. 
C)  Species produce more offspring than the environment can support. 
D)  Only a fraction of an individual's offspring may survive.

Question 15

Claytonia virginica is a plant with flowers that vary from white, to pale pink, to bright pink. Slugs prefer to eat pink-flowering over white-flowering plants (due to chemical differences between the two), and plants experiencing severe herbivory are more likely to die. The bees that pollinate this plant also prefer pink over white flowers, so that Claytonia with pink flowers produce more seeds than Claytonia with white flowers. A researcher observes that the percentage of different flower colors remains stable in the study population from year to year. Given no other information, if the researcher removes all slugs from the study population, what do you predict will most likely happen to the percentage of flower colors in the population over time?

Accepted Answer

A)  The percentage of pink flowers will increase over time. 
B)  The percentage of white flowers will increase over time. 
C)  The distribution of flower colors will not change. 
D)  The distribution of flower colors will randomly fluctuate over time. 
A)  The percentage of pink flowers will increase over time. 
B)  The percentage of white flowers will increase over time. 
C)  The distribution of flower colors will not change. 
D)  The distribution of flower colors will randomly fluctuate over time.

Question 16

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would be most likely to happen in environments that lack antibiotics?

Accepted Answer

A)  These bacteria would maintain the antibiotic-resistance genes in case the antibiotics reappear. 
B)  These bacteria would be outcompeted and replaced by bacteria that have lost the antibiotic resistance genes. 
C)  These bacteria would try to make the cost worthwhile by locating and migrating to microenvironments where traces of antibiotics are present. 
D)  These bacteria would increase the number of genes conveying antibiotic resistance. 
A)  These bacteria would maintain the antibiotic-resistance genes in case the antibiotics reappear. 
B)  These bacteria would be outcompeted and replaced by bacteria that have lost the antibiotic resistance genes. 
C)  These bacteria would try to make the cost worthwhile by locating and migrating to microenvironments where traces of antibiotics are present. 
D)  These bacteria would increase the number of genes conveying antibiotic resistance.

Question 17

Which of the following factors contribute to limiting the capacity of organisms to overreproduce?

Accepted Answer

A)  lack of food, mortality from predators, and production of many offspring per pair of parents 
B)  inability of individuals to tolerate the physical conditions, lack of food, and mortality from predators 
C)  abundance of food, mortality from predators, and inability of individuals to tolerate the physical conditions 
D)  inability of individuals to tolerate the physical conditions, production of many offspring per pair of parents, and abundance of food 
A)  lack of food, mortality from predators, and production of many offspring per pair of parents 
B)  inability of individuals to tolerate the physical conditions, lack of food, and mortality from predators 
C)  abundance of food, mortality from predators, and inability of individuals to tolerate the physical conditions 
D)  inability of individuals to tolerate the physical conditions, production of many offspring per pair of parents, and abundance of food

Question 18

Starting from the wild mustard Brassica oleracea, plant breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Which of the following statements is correct with regard to the wild mustard?

Accepted Answer

A)  There is enough heritable variation in the wild mustard to permit these different varieties. 
B)  Heritable variation is low in wild mustard-otherwise this wild strain would have different characteristics. 
C)  Natural selection is rare in wild populations of wild mustard. 
D)  In wild mustard, most of the variation is due to differences in soil or other aspects of the environment. 
A)  There is enough heritable variation in the wild mustard to permit these different varieties. 
B)  Heritable variation is low in wild mustard-otherwise this wild strain would have different characteristics. 
C)  Natural selection is rare in wild populations of wild mustard. 
D)  In wild mustard, most of the variation is due to differences in soil or other aspects of the environment.

Question 19

Which of the following factors would most likely cause an increase in population size of a prey animal?

Accepted Answer

A)  a decrease in available food 
B)  an increase in the number of predators 
C)  an improvement in eyesight 
D)  a reduction in camouflage 
A)  a decrease in available food 
B)  an increase in the number of predators 
C)  an improvement in eyesight 
D)  a reduction in camouflage

Question 20

Which of the following statements best describes evolution?

Accepted Answer

A)  Populations change genetically from one generation to the next. 
B)  The match between individuals and their environment decreases over time. 
C)  Natural selection favors the most abundant trait. 
D)  Individuals change in response to changes in the environment. 
A)  Populations change genetically from one generation to the next. 
B)  The match between individuals and their environment decreases over time. 
C)  Natural selection favors the most abundant trait. 
D)  Individuals change in response to changes in the environment.

Exam 21: How Evolution Works

Which of the following statements is most consistent with data obtained from the fossil record?

Within six months of effectively using methicillin to treat S. aureus infections in a community, all new S. aureus infections were caused by MRSA. How can this best be explained?

Emerald ash borers are beetles whose larvae eat the leaves of ash trees. Without treatment of the trees, the beetles usually kill all ash trees in an area within 10 years. Which of the following events would provide the best possible avenue for saving the ash trees?

Continental drift (plate tectonics) has moved continents around the globe. Which of the following predictions would be most likely?

Which of the following observations helped Darwin shape his concept of descent with modification?

Which of the following statements best describes the effect of natural selection on a population?

DDT was once considered a "silver bullet" that would permanently eradicate insect pests. Instead, DDT is now largely ineffective against many insects. Which of the following possible actions would have had the best chance of preventing this evolution of DDT resistance?

Which of the following statements best defines artificial selection?

The diagram is reminiscent of Darwin's sketch showing the branching of evolution. The horizontal axis of the diagram is a timeline that extends from 100,000 years ago to the present; the vertical axis represents nothing in particular. Which combination of ideas is represented in the diagram?

Which of the following statements about evolutionary trees is accurate?

Which of the following observations helped Darwin agree with Lyell that Earth was more than a few thousand years old?

Which of the following is not an observation or inference on which natural selection is based?

If the bacterium Staphylococcus aureus experiences a cost for maintaining one or more antibiotic-resistance genes, what would be most likely to happen in environments that lack antibiotics?

Which of the following factors contribute to limiting the capacity of organisms to overreproduce?

Starting from the wild mustard Brassica oleracea, plant breeders have created the strains known as Brussels sprouts, broccoli, kale, and cabbage. Which of the following statements is correct with regard to the wild mustard?

Which of the following factors would most likely cause an increase in population size of a prey animal?

Which of the following statements best describes evolution?

Biology and Its Themes

Atoms and Molecules

The Chemistry of Water

Carbon: the Basis of Molecular Diversity

Biological Macromolecules and Lipids

Energy and Life

Cell Structure and Function

Cell Membranes

Cellular Signaling

Cell Respiration

Photosynthetic Processes

Mitosis

Sexual Life Cycles and Meiosis

Mendelian Genetics

Linkage and Chromosomes

Nucleic Acids and Inheritance

Expression of Genes

Control of Gene Expression

Dna Technology

The Evolution of Genomes

Phylogenetic Reconstruction

Microevolution

Species and Speciation

Macroevolution

Introduction to Viruses

Prokaryotes

The Origin and Evolution of Eukaryotes

Nonvascular and Seedless Vascular Plants

Seed Plants

Introduction to Fungi

An Introduction to Animal Diversity

Invertebrates

Vertebrates

Plant Structure and Growth

Transport in Vascular Plants

Plant Nutrition

Reproduction of Flowering Plants

Plant Signals and Behavior

The Animal Body

Chemical Signals in Animals

Animal Digestive Systems

Animal Transport Systems

Animal Excretory Systems

Animal Reproductive Systems

Development in Animals

Animal Defenses Against Infection

Electrical Signals in Animals

Neural Regulation in Animals

Sensation and Movement in Animals

An Overview of Ecology

Behavioral Ecology

Populations and Life History Traits

Biodiversity and Communities

Energy Flow and Chemical Cycling in Ecosystems

Conservation and Global Ecology

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