1. Biology: Exploring Life
Chapter 1
Biology: Exploring Life
Lecture by Richard L. Myers

2. Introduction: Dining in the Trees
The leopard is an excellent example of an organism adapted to its environment
It survives because of adaptations to its environment
Examples are coat camouflage and hunting and climbing ability
Adaptations are the result of evolution
Evolution is the accumulation of genetic change over time that transforms life
Biology is the scientific study of life
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4. Ultimate Moms

6. THEMES IN THE STUDY OF BIOLOGY
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7. 1.1 In life’s hierarchy of organization, new properties emerge at each level
Life’s levels of organization define the scope of biology
Life emerges through organization of various levels
With addition of each new level, novel properties emerge—called emergent properties
During the study of biology, life should be considered from the molecular to the global level. An understanding of emergent properties allows one to appreciate the complexity and difficulty of understanding life as well as to appreciate life’s close association with the entire planet. Although emergent properties help explain the diversity of life, examples of emergent properties are not limited to life. Graphite and diamonds are both composed of carbon, but the carbons within them are arranged differently. The result is emergent properties that make the two very different.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. For a chance to add a little math to the biological levels of organization, consider calculating the general scale differences between each level of biological organization. For example, are cells generally 5, 10, 50, or 100 times larger than organelles? Are organelles generally 5, 10, 50, or 100 times larger than macromolecules? For some levels of organization, such as ecosystems, communities, and populations, size/scale differences are perhaps less relevant and more problematic to consider. However, at the smaller levels, the sense of scale might enhance an appreciation for levels of biological organization.
4. The U.S. Census Bureau maintains updated population clocks that estimate the U.S. and world populations on its website at If students have an accurate general idea of the population of the United States, statistics about the number of people affected with a disease or disaster become more significant. For example, the current population of the United States is approximately 305 million (2009). It is currently estimated that about one million people in the United States are infected with HIV. The number of people infected with HIV is impressive and concerning, but not perhaps as meaningful as realizing that the number of people infected represents one out of every 305 people in the United States. Although the infected people are not evenly distributed among geographic and ethnic groups, if you apply this generality to the enrollments in your classes, the students might better appreciate the tremendous impact of the infection.
Copyright © 2009 Pearson Education, Inc.

8. Biosphere Ecosystem Florida coast Community All organisms on
the Florida coast
Figure 1.1 Life’s hierarchy of organization.
Population
Group of brown
pelicans
Organism
Brown pelican

9. Organism Brown pelican Spinal cord Organ system Nervous system Brain
Nerve
Tissue
Nervous tissue
Atom
Figure 1.1 Life’s hierarchy of organization.
Cell
Nerve cell
Nucleus
Organelle
Nucleus
Molecule
DNA

10. 1.1 In life’s hierarchy of organization, new properties emerge at each level
The upper tier is a global perspective of life
Biosphere—all the environments on Earth that support life
Ecosystem—all the organisms living in a particular area
Community—a group of organisms living in a particular ecosystem
Population—all the individuals of a species within a specific area
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. For a chance to add a little math to the biological levels of organization, consider calculating the general scale differences between each level of biological organization. For example, are cells generally 5, 10, 50, or 100 times larger than organelles? Are organelles generally 5, 10, 50, or 100 times larger than macromolecules? For some levels of organization, such as ecosystems, communities, and populations, size/scale differences are perhaps less relevant and more problematic to consider. However, at the smaller levels, the sense of scale might enhance an appreciation for levels of biological organization.
4. The U.S. Census Bureau maintains updated population clocks that estimate the U.S. and world populations on its website at If students have an accurate general idea of the population of the United States, statistics about the number of people affected with a disease or disaster become more significant. For example, the current population of the United States is approximately 305 million (2009). It is currently estimated that about one million people in the United States are infected with HIV. The number of people infected with HIV is impressive and concerning, but not perhaps as meaningful as realizing that the number of people infected represents one out of every 305 people in the United States. Although the infected people are not evenly distributed among geographic and ethnic groups, if you apply this generality to the enrollments in your classes, the students might better appreciate the tremendous impact of the infection.
Copyright © 2009 Pearson Education, Inc.

11. 1.1 In life’s hierarchy of organization, new properties emerge at each level
The middle tier is characterized by the organism, an individual living thing, which is composed of
Organ systems—have specific functions; are composed of organs
Organs—provide specific functions for the organism
Tissues—made of groups of similar cells
Many organisms, such as protists, algae, and bacteria, are composed of microscopic individuals that exist as single cells.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. For a chance to add a little math to the biological levels of organization, consider calculating the general scale differences between each level of biological organization. For example, are cells generally 5, 10, 50, or 100 times larger than organelles? Are organelles generally 5, 10, 50, or 100 times larger than macromolecules? For some levels of organization, such as ecosystems, communities, and populations, size/scale differences are perhaps less relevant and more problematic to consider. However, at the smaller levels, the sense of scale might enhance an appreciation for levels of biological organization.
4. The U.S. Census Bureau maintains updated population clocks that estimate the U.S. and world populations on its website at If students have an accurate general idea of the population of the United States, statistics about the number of people affected with a disease or disaster become more significant. For example, the current population of the United States is approximately 305 million (2009). It is currently estimated that about one million people in the United States are infected with HIV. The number of people infected with HIV is impressive and concerning, but not perhaps as meaningful as realizing that the number of people infected represents one out of every 305 people in the United States. Although the infected people are not evenly distributed among geographic and ethnic groups, if you apply this generality to the enrollments in your classes, the students might better appreciate the tremendous impact of the infection.
Copyright © 2009 Pearson Education, Inc.

12. 1.1 In life’s hierarchy of organization, new properties emerge at each level
Life emerges at the level of the cell, the lower tier, which is composed of
Molecules—collections of atoms
Organelles—membrane-bound structures with specific functions
Cells—living entities separated from their environment by a membrane
A study of reductionism could be introduced at this point. Reductionism is the reduction of complex systems, such as an animal, to simpler components that are easier to study.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. For a chance to add a little math to the biological levels of organization, consider calculating the general scale differences between each level of biological organization. For example, are cells generally 5, 10, 50, or 100 times larger than organelles? Are organelles generally 5, 10, 50, or 100 times larger than macromolecules? For some levels of organization, such as ecosystems, communities, and populations, size/scale differences are perhaps less relevant and more problematic to consider. However, at the smaller levels, the sense of scale might enhance an appreciation for levels of biological organization.
4. The U.S. Census Bureau maintains updated population clocks that estimate the U.S. and world populations on its website at If students have an accurate general idea of the population of the United States, statistics about the number of people affected with a disease or disaster become more significant. For example, the current population of the United States is approximately 305 million (2009). It is currently estimated that about one million people in the United States are infected with HIV. The number of people infected with HIV is impressive and concerning, but not perhaps as meaningful as realizing that the number of people infected represents one out of every 305 people in the United States. Although the infected people are not evenly distributed among geographic and ethnic groups, if you apply this generality to the enrollments in your classes, the students might better appreciate the tremendous impact of the infection.
Copyright © 2009 Pearson Education, Inc.

13. 1.2 Living organisms interact with their environments, exchanging matter and energy
Life requires interactions between living and nonliving components
Photosynthetic organisms provide food and are called producers
Others eat plants (or animals that profit from plants) and are called consumers
The nonliving components are chemical nutrients required for life
The nonliving components are recycled and used over and over again. Carbon dioxide, oxygen, water, and various minerals are examples of components cycled within an ecosystem.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. Help the class think through the diverse interactions between an organism and its environment. In class, select an organism and have the class develop a list of environmental components that interact with the organism. Items in this list will likely fall into living and nonliving categories.
Copyright © 2009 Pearson Education, Inc.

14. 1.2 Living organisms interact with their environments, exchanging matter and energy
To be successful, an ecosystem must accomplish two things
Recycle chemicals necessary for life
Move energy through the ecosystem
Energy enters as light and exits as heat
The importance of plants and other photosynthetic organisms to ecosystem dynamics cannot be overstated.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. Help the class think through the diverse interactions between an organism and its environment. In class, select an organism and have the class develop a list of environmental components that interact with the organism. Items in this list will likely fall into living and nonliving categories.
Copyright © 2009 Pearson Education, Inc.

15. 1.3 Cells are the structural and functional units of life
Form generally fits function
By studying a biological structure, you determine what it does and how it works
Life emerges from interactions of structures
Combinations of structures (components) provide organization called a system
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. Help the class think through the diverse interactions between an organism and its environment. In class, select an organism and have the class develop a list of environmental components that interact with the organism. Items in this list will likely fall into living and nonliving categories.
4. Here is a simple way to contrast the relative size of prokaryotic and eukaryotic cells. Mitochondria and chloroplasts are thought to have evolved by endosymbiosis (see Chapter 16). Thus, mitochondria and chloroplasts are about the size of bacteria, contained within a plant cell. A figure of a plant cell therefore provides an immediate comparison of these sizes, not side-by-side, but one inside the other!
5. Examples of biological form and function relationships are nearly endless. Those immediately apparent to your students will be easiest to comprehend. Have your students examine (in photos or in specimens) the teeth of various vertebrates. The diet of these animals is implied by the shape of the teeth (sharp teeth in carnivorous cats and blunted molars in a rat). Sliding your tongue over your teeth reveals our omnivorous history, with sharp canine teeth for slicing flesh and flat rear molars well-suited for grinding plant material.
Copyright © 2009 Pearson Education, Inc.

16. 1.3 Cells are the structural and functional units of life
Two distinct groups of cells exist
Prokaryotic cells
Simple and small
Bacteria are prokaryotic
Eukaryotic cells
Possess organelles separated by membranes
Plants, animals, and fungi are eukaryotic
Regardless of the group studied, cells are enclosed by a membrane and use DNA as their genetic information.
Student Misconceptions and Concerns
1. Many students enter our courses with a limited appreciation of the diversity of life. Ask any group of freshmen at the start of the semester to write down the first type of animal that comes to mind, and the most frequent response is a mammal. As the diversity of life is explored, the common heritage of biological organization can be less, and not more, apparent. The diverse forms, habits, and ecological interactions overwhelm our senses with striking distinctions. Emphasizing the diversity as well as the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
2. We live in a world that is largely understood by what we can distinguish and identify with our naked senses. However, the diversity of life and the levels of biological organization extend well below the physical scale of our lives. For many students, appreciating the diversity of the microscopic world is abstract, nearly on par with an understanding of the workings of atoms and molecules. The ability to examine the microscopic details of the world of our students (the surface of potato chips, the structure of table salt and sugar, the details of a blade of grass) can be an important sensory extension that prepares the mind for greater comprehension of these minute biological details.
Teaching Tips
1. Consider asking students to bring to class a page or two of some article about biology that appeared in the media in the last month. Alternatively, you could have each student a Web address of a recent biology-related news event to you. You might even have them relevant articles to you for each of the main topics you address throughout the semester.
2. The scientific organization Sigma Xi offers a free summary of the major science news articles appearing each weekday in major U.S. news media. The first paragraph or so of each article is included in the with a hyperlink to the rest of the article. The diverse topics are an excellent way to learn of general scientific announcements and reports. Typically, 5–10 articles are cited in each . To sign up for this free service, go to
3. Help the class think through the diverse interactions between an organism and its environment. In class, select an organism and have the class develop a list of environmental components that interact with the organism. Items in this list will likely fall into living and nonliving categories.
4. Here is a simple way to contrast the relative size of prokaryotic and eukaryotic cells. Mitochondria and chloroplasts are thought to have evolved by endosymbiosis (see Chapter 16). Thus, mitochondria and chloroplasts are about the size of bacteria, contained within a plant cell. A figure of a plant cell therefore provides an immediate comparison of these sizes, not side-by-side, but one inside the other!
5. Examples of biological form and function relationships are nearly endless. Those immediately apparent to your students will be easiest to comprehend. Have your students examine (in photos or in specimens) the teeth of various vertebrates. The diet of these animals is implied by the shape of the teeth (sharp teeth in carnivorous cats and blunted molars in a rat). Sliding your tongue over your teeth reveals our omnivorous history, with sharp canine teeth for slicing flesh and flat rear molars well-suited for grinding plant material.
Copyright © 2009 Pearson Education, Inc.

17. Prokaryotic cell Eukaryotic cell DNA (no nucleus) Membrane Nucleus
Figure 1.3 Contrasting the size and complexity of prokaryotic and eukaryotic cells.
This figure indicates that the eukaryotic cell is subdivided into functional compartments (organelles) by membranes.
Nucleus
(contains DNA)
Organelles

18. EVOLUTION, THE CORE THEME OF BIOLOGY
Copyright © 2009 Pearson Education, Inc.

19. 1.4 The unity of life: All forms of life have common features
DNA is the genetic (hereditary) material of all cells
A gene is a distinct unit of DNA
The chemical structure of DNA accounts for its function
The diversity of life results from differences in DNA structure from individual to individual
Teaching Tips
1. The authors make an analogy between the four bases used to form genes and the 26 letters of the English alphabet used to create words and sentences. One could also make an analogy between the four bases and trains composed of four different types of railroad cars (perhaps an engine, boxcar, tanker, and caboose). Imagine how many different types of trains one could make using just 100 rail cars of four different types. (The answer is 4100.)
2. The seven characteristics of life described in Module 1.4 can easily become another list to memorize. Exercises that require reflection and analysis of these significant traits can help to make this list more meaningful. Consider creating examples of each of these properties for students to analyze and identify.
Copyright © 2009 Pearson Education, Inc.

20. (b) Single strand of DNA
Nucleus
DNA
Nucleotide
Cell
Campbell, Neil, and Jane Reece, Biology, 8th ed., Figure 1.10 DNA: The genetic material; (a) DNA double helix, (b) Single strand of DNA.
(a) DNA double helix
(b) Single strand of DNA

21. 1.4 The unity of life: All forms of life have common features

22. 1.4 The unity of life: All forms of life have common features
All living things share common properties
Order—the complex organization of living things
Regulation—an ability to maintain an internal environment consistent with life
Growth and development—consistent growth and development controlled by DNA
Energy processing—acquiring energy and transforming it to a form useful for the organism
Teaching Tips
1. The authors make an analogy between the four bases used to form genes and the 26 letters of the English alphabet used to create words and sentences. One could also make an analogy between the four bases and trains composed of four different types of railroad cars (perhaps an engine, boxcar, tanker, and caboose). Imagine how many different types of trains one could make using just 100 rail cars of four different types. (The answer is 4100.)
2. The seven characteristics of life described in Module 1.4 can easily become another list to memorize. Exercises that require reflection and analysis of these significant traits can help to make this list more meaningful. Consider creating examples of each of these properties for students to analyze and identify.
Copyright © 2009 Pearson Education, Inc.

23. 1.4 The unity of life: All forms of life have common features
Common properties continued
Response to the environment—an ability to respond to environmental stimuli
Reproduction—the ability to perpetuate the species
Evolutionary adaptation—acquisition of traits that best suit the organism to its environment
These common properties separate life forms from Earth’s other forms. Viruses, for example, are very important infectious agents but, because they do not share all of the properties listed here, are not considered “living.” Not all viruses have DNA; some use RNA as their genetic information. Viruses cannot generate energy through metabolism, but rather depend upon host cells for their energy needs.
Teaching Tips
1. The authors make an analogy between the four bases used to form genes and the 26 letters of the English alphabet used to create words and sentences. One could also make an analogy between the four bases and trains composed of four different types of railroad cars (perhaps an engine, boxcar, tanker, and caboose). Imagine how many different types of trains one could make using just 100 rail cars of four different types. (The answer is 4100.)
2. The seven characteristics of life described in Module 1.4 can easily become another list to memorize. Exercises that require reflection and analysis of these significant traits can help to make this list more meaningful. Consider creating examples of each of these properties for students to analyze and identify.
Video: Sea Horses
Copyright © 2009 Pearson Education, Inc.

24. 1.5 The diversity of life can be arranged into three domains
The three domains (groups) of life
Bacteria—prokaryotic, and most are unicellular and microscopic
Archaea—like bacteria, are prokaryotic, and most are unicellular and microscopic
Eukarya—are eukaryotic and contain a nucleus and organelles
Archaea live in unusual places, such as thermal vents in deep oceans, in hot springs and even in places where they are continually exposed to an extreme pH. Some scientists believe that these environments mimic early Earth and suggest that Archaea may be reminiscent of early forms of life.
You may want to give a brief definition of species, which is discussed in detail in Chapter 14.
Teaching Tips
1. An excellent introduction to the domains and kingdoms of life is presented at
Copyright © 2009 Pearson Education, Inc.

25. Figure 1.5A Drawers of diversity: some of the tens of thousands of species in the moth and butterfly collection at the National Museum of Natural History in Washington, D.C.

26. Domain Eukarya Domain Bacteria Domain Archaea
Bacteria (multiple kingdoms)
Protists (multiple kingdoms)
Kingdom Plantae
Domain Archaea
Figure 1.5B The three domains of life.
Archaea (multiple kingdoms)
Kingdom Fungi
Kingdom Animalia

27. 1.6 Evolution explains the unity and diversity of life
In 1859, Charles Darwin published On the Origin of Species by Means of Natural Selection
The book accomplished two things
Presented evidence to support the idea of evolution
Proposed a mechanism for evolution called natural selection
Student Misconceptions and Concerns
1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures deliberately or out of want or need, and individuals do not evolve. Evolution is a passive process in which the environment favors one or more variations of a trait that naturally exist within a population.
2. Students often believe that Charles Darwin was the first to suggest that life evolves; the early contributions by Greek philosophers and the work of Jean-Baptiste de Lamarck and others may be unappreciated. Consider emphasizing this earlier work in your introduction to Darwin’s contributions.
Teaching Tips
1. Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. Texts of The Voyage of the Beagle, The Origin of Species (first and sixth editions), and The Descent of Man can be found at
c. Details about Charles Darwin’s home are located at
d. An extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
2. Many games model aspects of natural selection. Here is one that is appropriate for a laboratory exercise. Purchase several bags of dried grocery store beans of diverse sizes and colors. Large lima beans, small white beans, red beans, and black beans are all good options. Consider the beans food for the “predatory” students. To begin, randomly distribute (throw) 100 beans of each of four colors onto a green lawn. Allow individual students to collect beans over a set period, perhaps 2 minutes. Then count the total number of each color of bean collected. Assume that the beans remaining undetected (still in the lawn) reproduce by doubling in number. Calculate the number of beans of each color remaining in the field. For the next round, count out the number of each color to add to the lawn such that the new totals on the lawn will double the number of beans that students did not find in the first “generation”. Before each predatory episode, record the total number of each color of beans that have “survived” in the field. Then let your student predators search for another round (generation). Repeat the process for at least three or four generations. Note what colors of beans have been favored by the environment. Apply Darwin’s observations and inferences to this exercise. Ask students to speculate which colors might have been favored during another season of the year or in another location, such as a parking lot.
Video: Galapágos Island Overview
Video: Galapágos Sea Lion
Video: Galapágos Marine Iguana
Video: Galapágos Tortoise
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28. Campbell, Neil, and Jane Reece, Biology, 8th ed. , Figure 1
Campbell, Neil, and Jane Reece, Biology, 8th ed., Figure 1.18 Charles Darwin as a young man.

29. 1.6 Evolution explains the unity and diversity of life
Natural selection was inferred by connecting two observations
Individuals within a population inherit different characteristics and vary from other individuals
A particular population of individuals produces more offspring than will survive to produce offspring of their own
Student Misconceptions and Concerns
1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures deliberately or out of want or need, and individuals do not evolve. Evolution is a passive process in which the environment favors one or more variations of a trait that naturally exist within a population.
2. Students often believe that Charles Darwin was the first to suggest that life evolves; the early contributions by Greek philosophers and the work of Jean-Baptiste de Lamarck and others may be unappreciated. Consider emphasizing this earlier work in your introduction to Darwin’s contributions.
Teaching Tips
1. Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. Texts of The Voyage of the Beagle, The Origin of Species (first and sixth editions), and The Descent of Man can be found at
c. Details about Charles Darwin’s home are located at
d. An extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
2. Many games model aspects of natural selection. Here is one that is appropriate for a laboratory exercise. Purchase several bags of dried grocery store beans of diverse sizes and colors. Large lima beans, small white beans, red beans, and black beans are all good options. Consider the beans food for the “predatory” students. To begin, randomly distribute (throw) 100 beans of each of four colors onto a green lawn. Allow individual students to collect beans over a set period, perhaps 2 minutes. Then count the total number of each color of bean collected. Assume that the beans remaining undetected (still in the lawn) reproduce by doubling in number. Calculate the number of beans of each color remaining in the field. For the next round, count out the number of each color to add to the lawn such that the new totals on the lawn will double the number of beans that students did not find in the first “generation”. Before each predatory episode, record the total number of each color of beans that have “survived” in the field. Then let your student predators search for another round (generation). Repeat the process for at least three or four generations. Note what colors of beans have been favored by the environment. Apply Darwin’s observations and inferences to this exercise. Ask students to speculate which colors might have been favored during another season of the year or in another location, such as a parking lot.
Video: Blue-footed Boobies Courtship Ritual
Video: Albatross Courtship Ritual
Video: Soaring Hawk
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30. 1.6 Evolution explains the unity and diversity of life
Natural selection is an editing mechanism
It results from exposure of heritable variations to environmental factors that favor some individuals over others
Over time this results in evolution of new species adapted to particular environments
Evolution is biology’s core theme and explains unity and diversity of life
Student Misconceptions and Concerns
1. Students often misunderstand the basic process of evolution and instead express a Lamarckian point of view. Organisms do not evolve structures deliberately or out of want or need, and individuals do not evolve. Evolution is a passive process in which the environment favors one or more variations of a trait that naturally exist within a population.
2. Students often believe that Charles Darwin was the first to suggest that life evolves; the early contributions by Greek philosophers and the work of Jean-Baptiste de Lamarck and others may be unappreciated. Consider emphasizing this earlier work in your introduction to Darwin’s contributions.
Teaching Tips
1. Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. Texts of The Voyage of the Beagle, The Origin of Species (first and sixth editions), and The Descent of Man can be found at
c. Details about Charles Darwin’s home are located at
d. An extensive usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
2. Many games model aspects of natural selection. Here is one that is appropriate for a laboratory exercise. Purchase several bags of dried grocery store beans of diverse sizes and colors. Large lima beans, small white beans, red beans, and black beans are all good options. Consider the beans food for the “predatory” students. To begin, randomly distribute (throw) 100 beans of each of four colors onto a green lawn. Allow individual students to collect beans over a set period, perhaps 2 minutes. Then count the total number of each color of bean collected. Assume that the
beans remaining undetected (still in the lawn) reproduce by doubling in number. Calculate the number of beans of each color remaining in the field. For the next round, count out the number of each color to add to the lawn such that the new totals on the lawn will double the number of beans that students did not find in the first “generation”. Before each predatory episode, record the total number of each color of beans that have “survived” in the field. Then let your student predators search for another round (generation). Repeat the process for at least three or four generations. Note what colors of beans have been favored by the environment. Apply Darwin’s observations and inferences to this exercise. Ask students to speculate which colors might have been favored during another season of the year or in another location, such as a parking lot.
Copyright © 2009 Pearson Education, Inc.

31. Population with varied inherited traits1
Population with varied inherited traits 2
Elimination of individuals with certain traits
Figure 1.6B An example of natural selection in action. 3
Reproduction of survivors

32. Inferences Observations Natural selection: unequal reproductive
success
Individual
variation
Overproduction
of offspring
Evolution
of adaptations
in a population

33. Figure 1.6C Examples of adaptations to different environments.
Killer whale
Pangolin

34. THE PROCESS OF SCIENCE
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35. 1.7 Scientists use two main approaches to learn about nature
Two approaches are used to understand natural causes for natural phenomena
Discovery science—uses verifiable observations and measurements to describe science
Hypothesis-based science—uses the data from discovery science to explain science
This requires proposing and testing of hypotheses
Inquiry is at the heart of science, and scientists conduct research on a variety of specific questions. Inquisition drives science.
Student Misconceptions and Concerns
1. The authors’ distinction between natural and supernatural explanations is essential to understanding the power and limits of scientific explanations. This distinction is important when distinguishing between science and supernatural explanations for the origin of life and the generation of biodiversity.
2. Contrasting the concept of faith with the tentative nature of science can help to define and distinguish science from other ways of knowing. Students sometimes enter science classes expecting absolutes of facts and rigid dogma. Instead, scientific knowledge reflects degrees of confidence closely correlated to the strength of evidence.
3. The common use of the terms law and theory often blur the stricter definitions of these terms in science. In general, laws describe and theories explain. Both are typically well-established concepts in science. A free online publication by the National Academy of Sciences helps to define these and related terms more carefully. See Chapter 1 of Teaching About Evolution and the Nature of Science at
Teaching Tips
1. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.
Copyright © 2009 Pearson Education, Inc.

36. 1.7 Scientists use two main approaches to learn about nature
There is a difference between a theory and a hypothesis
A hypothesis is a proposed explanation for a set of observations
A theory is supported by a large and usually growing body of evidence
Most nonscientists think of a theory as being nothing more than a “hunch.” Actually, a theory is accepted by most scientists as being factual. For example, the theory of relativity and the theory of evolution are supported by a significant amount of factual data.
Student Misconceptions and Concerns
1. The authors’ distinction between natural and supernatural explanations is essential to understanding the power and limits of scientific explanations. This distinction is important when distinguishing between science and supernatural explanations for the origin of life and the generation of biodiversity.
2. Contrasting the concept of faith with the tentative nature of science can help to define and distinguish science from other ways of knowing. Students sometimes enter science classes expecting absolutes of facts and rigid dogma. Instead, scientific knowledge reflects degrees of confidence closely correlated to the strength of evidence.
3. The common use of the terms law and theory often blur the stricter definitions of these terms in science. In general, laws describe and theories explain. Both are typically well-established concepts in science. A free online publication by the National Academy of Sciences helps to define these and related terms more carefully. See Chapter 1 of Teaching About Evolution and the Nature of Science at
Teaching Tips
1. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.
Copyright © 2009 Pearson Education, Inc.

37. 1.8 With hypothesis-based science, we pose and test hypotheses
We solve everyday problems by using hypotheses
An example would be the reasoning we use to answer the question, “Why doesn’t the flashlight work?”
Using deductive reasoning we realize that the problem is either the (1) bulb or (2) batteries.
The hypothesis must be testable
The hypothesis must be falsifiable
A hypothesis must be testable—find ways to check the validity of the idea. A hypothesis must also be falsifiable—find ways to reveal whether such an idea is actually not true.
Teaching Tips
1. Consider using a laboratory exercise to have your students plan and perhaps conduct investigations using discovery science and/or investigations using a hypothesis-driven approach. Emphasize the processes and not the significance of the questions. Students can conduct descriptive surveys of student behavior (use of pens or pencils for taking notes, use of backpacks) or test hypotheses using controlled trials. Students will need some supervision and advice while planning and conducting their experiments.
2. Consider presenting your class with descriptions of several scientific investigations that you have written or found described in the media. Edit or include numerous examples of improper methodology (small sample size, several variables existing between the control and experimental groups, failure to specifically test the hypothesis, etc.). Let small groups or individuals analyze the experiments in class to identify the flaws. This critical analysis allows students the opportunity to suggest the characteristics of good investigations in class.
3. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.
Copyright © 2009 Pearson Education, Inc.

38. Figure 1.8A An example of hypothesis-based science.
Observations
Question
Hypothesis #1:
Dead batteries
Hypothesis #2:
Burned-out bulb
Figure 1.8A An example of hypothesis-based science.

39. Figure 1.8A An example of hypothesis-based science.
Observations
Question
Hypothesis #1:
Dead batteries
Hypothesis #2:
Burned-out bulb
Prediction:
Replacing batteries
will fix problem
Prediction:
Replacing bulb
will fix problem
Figure 1.8A An example of hypothesis-based science.
Test prediction
Test prediction

40. Test falsifies hypothesis
Observations
Question
Hypothesis #1:
Dead batteries
Hypothesis #2:
Burned-out bulb
Prediction:
Replacing batteries
will fix problem
Prediction:
Replacing bulb
will fix problem
Figure 1.8A An example of hypothesis-based science.
Test prediction
Test prediction
Test falsifies hypothesis
Test does not falsify hypothesis

41. 1.8 With hypothesis-based science, we pose and test hypotheses
Another hypothesis: Mimicry helps protect nonpoisonous king snakes from predators where poisonous coral snakes also live
The hypothesis predicts that predators learn to avoid the warning coloration of coral snakes
Teaching Tips
1. Consider using a laboratory exercise to have your students plan and perhaps conduct investigations using discovery science and/or investigations using a hypothesis-driven approach. Emphasize the processes and not the significance of the questions. Students can conduct descriptive surveys of student behavior (use of pens or pencils for taking notes, use of backpacks) or test hypotheses using controlled trials. Students will need some supervision and advice while planning and conducting their experiments.
2. Consider presenting your class with descriptions of several scientific investigations that you have written or found described in the media. Edit or include numerous examples of improper methodology (small sample size, several variables existing between the control and experimental groups, failure to specifically test the hypothesis, etc.). Let small groups or individuals analyze the experiments in class to identify the flaws. This critical analysis allows students the opportunity to suggest the characteristics of good investigations in class.
3. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.
Copyright © 2009 Pearson Education, Inc.

42. 1.8 With hypothesis-based science, we pose and test hypotheses
Experimentation supports the prediction of the mimicry hypothesis—nonpoisonous snakes that mimic coloration of coral snakes are attacked less frequently
The experiment has a control group using brown artificial snakes for comparison
The experimental group is artificial snakes with the red, black, and yellow ring pattern of king snakes
The control group is the part of scientific inquiry that acts as a basis of comparison. The experimental group adds variables that will prove or disprove the hypothesis.
Teaching Tips
1. Consider using a laboratory exercise to have your students plan and perhaps conduct investigations using discovery science and/or investigations using a hypothesis-driven approach. Emphasize the processes and not the significance of the questions. Students can conduct descriptive surveys of student behavior (use of pens or pencils for taking notes, use of backpacks) or test hypotheses using controlled trials. Students will need some supervision and advice while planning and conducting their experiments.
2. Consider presenting your class with descriptions of several scientific investigations that you have written or found described in the media. Edit or include numerous examples of improper methodology (small sample size, several variables existing between the control and experimental groups, failure to specifically test the hypothesis, etc.). Let small groups or individuals analyze the experiments in class to identify the flaws. This critical analysis allows students the opportunity to suggest the characteristics of good investigations in class.
3. Have your students explain why a coordinated conspiracy promoting a specific idea in science is unlikely to succeed. Have your students describe aspects of science that would check fraudulent or erroneous claims and/or political efforts.
Copyright © 2009 Pearson Education, Inc.

43. Figure 1.8B Eastern coral snake (poisonous).

44. Figure 1.8C Scarlet king snake (nonpoisonous).

45. Figure 1.8D Artificial king snake that was not attacked (left); artificial brown snake that was attacked by a bear (right).

46. Percent of total attacks
100
Artificial
king snakes
83%
84% 80
Artificial
brown snakes 60
Percent of total attacks
on artificial snakes 40 20
17%
Figure 1.8E Results of mimicry experiment.
16%
Coral snakes
absent
Coral snakes
present

47. BIOLOGY AND EVERYDAY LIFE
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48. 1.9 CONNECTION: Biology, technology, and society are connected in important ways
Many of today’s global issues relate to biology (science)
Many of these issues resulted from applications of technology
Science and technology are interdependent, but their goals differ
Science wants to understand natural phenomena
Technology applies science for a specific purpose
Scientists learned that an individual’s DNA is composed of specific sequences of nucleotides that produce a DNA “fingerprint.” Due to technology, it is possible to “fingerprint” an individual and use this information to identify him/her. Therefore, science looked for answers to genetic questions, while technology applied this knowledge for a specific purpose.
Student Misconceptions and Concerns
1. Many students will be unable to distinguish between science and technology. The discussion in Module 1.9 makes several distinctions worth emphasizing for students who may struggle to read and understand the textbook.
Teaching Tips
1. Looking around your classroom, consider immediate examples of technology. Perhaps a video projector, a telephone, a wall clock, or other devices are available for quick reference. Then challenge your students to suggest examples of science in their immediate world. (These might include dietary guidelines, other suggestions to improve health and fitness, and medications.)
Copyright © 2009 Pearson Education, Inc.

49. 1.10 EVOLUTION CONNECTION: Evolution is connected to our everyday lives
How is evolution connected to our everyday lives?
It explains how all living species descended from ancestral species
Differences between DNA of individuals, species, and populations reflect evolutionary change
The environment matters because it is a selective force that drives evolution
An understanding of evolution helps us fight disease and develop conservation efforts
Student Misconceptions and Concerns
1. Few students are likely to understand the tremendous benefits that result from an understanding of evolution. Evolution may seem like an abstract concept that is still up for debate. Yet evolution is a daily part of our lives, recognized or not.
Teaching Tips
1. Module 1.10 lists many of the major human challenges impacted by evolution. Our ability to feed ourselves, respond to infectious disease, and understand the interrelationships of our crops, agricultural animals, pets, and each other, are all enriched by an appreciation of evolution. Understanding evolution lets us work more deliberately in our evolving world.
Copyright © 2009 Pearson Education, Inc.