1. Ch. 1: Exploring Life
Figure Why do so many animals match their surroundings?

2. THEMES IN THE STUDY OF BIOLOGY
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3. 1.1 All forms of life share common properties
Biology is the scientific study of life.
Properties of life include
Order—the highly ordered structure that typifies life,
Reproduction—the ability of organisms to reproduce their own kind,
Growth and development—consistent growth and development controlled by inherited DNA,
Energy processing—the use of chemical energy to power an organism’s activities and chemical reactions,
Student Misconceptions and Concerns
• 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 and the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
• 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 scale of our unaided perceptions. 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
• 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 might have each student post a recent biology-related news article on a course website.
• 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 in the national media. Typically, 5–10 articles are cited in each . To sign up for this free service, go to and sign up for the Sigma Xi Smart Brief.
Active Teaching Tips
Consider asking students to pair up with someone sitting near them to identify examples of the seven properties of life in some organism from your region (or perhaps a school mascot, if appropriate).
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4. 1.1 All forms of life share common properties
Regulation—an ability to control an organism’s internal environment within limits that sustain life,
Response to the environment—an ability to respond to environmental stimuli, and
Evolutionary adaptation—adaptations evolve over many generations, as individuals with traits best suited to their environments have greater reproductive success and pass their traits to offspring.
Student Misconceptions and Concerns
• 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 and the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
• 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 scale of our unaided perceptions. 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
• 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 might have each student post a recent biology-related news article on a course website.
• 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 in the national media. Typically, 5–10 articles are cited in each . To sign up for this free service, go to and sign up for the Sigma Xi Smart Brief.
Active Teaching Tips
Consider asking students to pair up with someone sitting near them to identify examples of the seven properties of life in some organism from your region (or perhaps a school mascot, if appropriate).
© 2015 Pearson Education, Inc. 4

5. (3) Growth and development (6) Response to the environment
Figure 1.1-0
(1) Order
(2) Reproduction
(3) Growth and development
(4) Energy processing
Figure Some important properties of life
(5) Regulation
(6) Response to the environment
(7) Evolutionary adaptation

6. Biosphere
Ecosystem Florida Everglades
1.2 In life’s hierarchy of organization, new properties emerge at each level
Emergent properties are new properties that arise in each step upward in the hierarchy of life from the arrangement and interactions among component parts.
Florida
Community All organisms in this wetland ecosystem
Population All alligators living in the wetlands
Organism an American alligator
Spinal cord
Nerve
Organ system Nervous system
Figure Life’s hierarchy of organization
Brain
Organ Brain
Tissue Nervous tissue
Atom
Cell Nerve cell
Nucleus
Organelle Nucleus
Molecule DNA 6

7. 1.3 Cells are the structural and functional units of life
A cell can
regulate its internal environment,
take in and use energy,
respond to its environment,
develop and maintain its complex organization, and
give rise to new cells.
Student Misconceptions and Concerns
• 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 and the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
• 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 scale of our unaided perceptions. 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
• 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 might have each student post a recent biology-related news article on a course website.
• 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 in the national media. Typically, 5–10 articles are cited in each . To sign up for this free service, go to and sign up for the Sigma Xi Smart Brief.
• 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. 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!
• 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.
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8. Nucleus (membrane- enclosed)
Figure 1.3
Prokaryotic cell
DNA (no nucleus)
Eukaryotic cell
Membrane
Organelles
Nucleus (membrane- enclosed)
Figure 1.3 Contrasting the size and complexity of prokaryotic and eukaryotic cells
DNA (throughout nucleus)

9. 1.4 Organisms interact with their environment, exchanging matter and energy
Living organisms interact with their environments, which include other organisms and physical factors.
The dynamics of ecosystems include two major processes:
the recycling of chemical nutrients from the atmosphere and soil through producers, consumers, and decomposers back to the air and soil and
the one-way flow of energy through an ecosystem, entering as sunlight and exiting as heat.
Student Misconceptions and Concerns
• 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 and the unifying aspects of life is necessary for a greater understanding of the rich evolutionary history of life on Earth.
• 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 scale of our unaided perceptions. 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
• 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 might have each student post a recent biology-related news article on a course website.
• 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 in the national media. Typically, 5–10 articles are cited in each . To sign up for this free service, go to and sign up for the Sigma Xi Smart Brief.
• 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.
• Perhaps you have seen and can find a photo of a glass-enclosed miniature ecosystem, likely containing some plants and shrimp. These are sometimes called a “shrimp biosphere,” “Aqua-Biosphere,” or “Ecosphere.” Present this system to your students and challenge them to explain the dynamics of energy and nutrients in this system. Such an analysis will reveal that energy flows through but nutrients cycle within this system.
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10. Chemical energy in food
Figure 1.4-0
ENERGY FLOW
Sun
Inflow of light energy
Outflow of heat
Consumers (animals)
Producers (plants)
Figure The cycling of nutrients and flow of energy in an ecosystem
Chemical energy in food
Leaves take up CO2 from air; roots absorb H2O and minerals from soil
Decomposers such as worms, fungi, and bacteria return chemicals to soil 10

11. Evolution, the Core Theme of Biology
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12. 1.5 The unity of life is based on DNA and a common genetic code
All cells have DNA, the chemical substance of genes.
All forms of life use essentially the same code to translate the information stored in DNA into proteins.
The diversity of life arises from differences in DNA sequences.
Student Misconceptions and Concerns
• Students likely have heard the terms chromosome, DNA, and gene. But distinguishing between a chromosome and DNA is often difficult for students, and defining a gene has been problematic even for scientists. Consider spending additional time to distinguish between these terms and note how our understanding has dramatically changed in the last 60 years.
Teaching Tips
• 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 flatbed). Imagine how many different types of trains one could make using just 100 rail cars of four different types. (The answer is 4100.)
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13. Cell Nucleus DNA Figure 1.5-0T A A T C G A T
Figure The four building blocks of DNA (left); part of a DNA double helix (right) T A A C G G C T C G C A T A T G T A

14. 1.6 The diversity of life can be arranged into three domains
The diversity of life can be arranged into three higher levels called domains.
Bacteria are the most diverse and widespread prokaryotes.
Archaea are prokaryotes that often live in Earth’s extreme environments.
Eukarya have eukaryotic cells and include
single-celled protists and
multicellular fungi, animals, & plants.
Student Misconceptions and Concerns
• As noted in the text, the classification of life has changed significantly in recent years. Many of your students may have used outdated materials in high school, increasingly common in difficult financial times. Therefore, the current descriptions may be contrary to schemes already understood by your students. Noting these revisions in classification can also be an opportunity to reflect on the nature of science, as new information is used to revise our understandings.
Teaching Tips
• An excellent introduction to the domains and kingdoms of life is presented at
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15. Protists (multiple kingdoms) Kingdom Plantae Domain Archaea
Figure 1.6-0
Domain Bacteria
Domain Eukarya
Bacteria
Protists (multiple kingdoms)
Kingdom Plantae
Domain Archaea
Figure The three domains of life
Archaea
Kingdom Fungi
Kingdom Animalia

16. 1.7 Evolution explains the unity and diversity of life
Evolution: the process of change that has transformed life on Earth from its earliest beginnings to the diversity of organisms living today.
The fossil record documents
that life has been evolving on Earth for billions of years and
the pattern of ancestry.
Student Misconceptions and Concerns
• 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.
• 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
• Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. An outstanding source for Darwin’s writings and other resources can be found at
c. The complete works of Charles Darwin can be found at
d. Details about Charles Darwin’s home are located at
e. An extensive Usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
• 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 toss out the new beans and 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, perhaps after a deep snowfall, or in another location, such as a parking lot.
Active Lecture Tips
• See the Activity What is That Adapted For? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
• See the Activity What Do My Classmates Think About Evolution? What Do Scientists Believe About Religion? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
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17. 1.7 Evolution explains the unity and diversity of life
In 1859, Charles Darwin published the book On the Origin of Species by Means of Natural Selection, which articulated two main points.
Species living today descended from ancestral species in what Darwin called “descent with modification.”
Natural selection is a mechanism for evolution.
Student Misconceptions and Concerns
• 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.
• 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
• Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. An outstanding source for Darwin’s writings and other resources can be found at
c. The complete works of Charles Darwin can be found at
d. Details about Charles Darwin’s home are located at
e. An extensive Usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
• 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 toss out the new beans and 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, perhaps after a deep snowfall, or in another location, such as a parking lot.
Active Lecture Tips
• See the Activity What is That Adapted For? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
• See the Activity What Do My Classmates Think About Evolution? What Do Scientists Believe About Religion? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
© 2015 Pearson Education, Inc. 17

18. Population with varied inherited traits.
Figure 1.7d-3 1
Population with varied
inherited traits. 2
Elimination of individuals with certain traits and reproduction of survivors. 3
Increasing frequency of traits that enhance survival and reproductive success.
Figure 1.7d-3 An example of natural selection in action (step 3)

19. 1.7 Evolution explains the unity and diversity of life
Darwin realized that numerous small changes in populations as a result of natural selection could eventually lead to major alterations of species.
The fossil record provides evidence of such diversification of species from ancestral species.
Student Misconceptions and Concerns
• 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.
• 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
• Many resources related to Charles Darwin are available on the Internet.
a. General evolution resources:
b. An outstanding source for Darwin’s writings and other resources can be found at
c. The complete works of Charles Darwin can be found at
d. Details about Charles Darwin’s home are located at
e. An extensive Usenet newsgroup devoted to the discussion and debate of biological and physical origins is at
• 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 toss out the new beans and 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, perhaps after a deep snowfall, or in another location, such as a parking lot.
Active Lecture Tips
• See the Activity What is That Adapted For? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
• See the Activity What Do My Classmates Think About Evolution? What Do Scientists Believe About Religion? on the Instructor Exchange. Visit the Instructor Exchange in the MasteringBiology instructor resource area for a description of this activity.
© 2015 Pearson Education, Inc. 19