By the end of this section, you will be able to:Explain what a correlation coefficient tells us about the relationship between variablesRecognize that correlation does not indicate a cause-and-effect relationship between variablesDiscuss our tendency to look for relationships between variables that do not really existExplain random sampling and assignment of participants into experimental and control groupsDiscuss how experimenter or participant bias could affect the results of an experimentIdentify independent and dependent variables

Biology is designed for multi-semester biology courses for science majors. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

Biology is designed for multi-semester biology courses for science majors. This version has been adapted by faculty at Austin Community College. It is grounded on an evolutionary basis and includes exciting features that highlight careers in the biological sciences and everyday applications of the concepts at hand. To meet the needs of today’s instructors and students, some content has been strategically condensed while maintaining the overall scope and coverage of traditional texts for this course. Instructors can customize the book, adapting it to the approach that works best in their classroom. Biology also includes an innovative art program that incorporates critical thinking and clicker questions to help students understand—and apply—key concepts.

Life is all around us, both as multicellular organisms such as the iguana and bamboo above, as well as the unicellular microorganisms such as bacteria.  Life is present on every continent, in the air and in the waters of the world.  There is life even in the Mariana Trench, seven miles below the surface of the ocean.  As of 2010 biologists have described and classified 1.7 million plants and animals, and estimate that there are till over five million species still undiscovered.This chapter will introduce the ways we study the science of Biology in the twenty-first century, the characteristics of living organisms and their classification.

What is biology? In simple terms, biology is the study of living organisms and their interactions with one another and their environments. This is a very broad definition because the scope of biology is vast. Biologists may study anything from the microscopic or submicroscopic view of a cell to ecosystems and the whole living planet (Figure 1.2). Listening to the daily news, you will quickly realize how many aspects of biology are discussed every day. For example, recent news topics include Escherichia coli (Figure 1.3) outbreaks in spinach and Salmonella contamination in peanut butter. Other subjects include efforts toward finding a cure for AIDS, Alzheimer’s disease, and cancer. On a global scale, many researchers are committed to finding ways to protect the planet, solve environmental issues, and reduce the effects of climate change. All of these diverse endeavors are related to different facets of the discipline of biology.

Biologists study the living world by posing questions about it and seeking science-based responses. This approach is common to other sciences as well and is often referred to as the scientific method. The scientific method was used even in ancient times, but it was first documented by England’s Sir Francis Bacon (1561–1626) (Figure 1.5), who set up inductive methods for scientific inquiry. The scientific method is not exclusively used by biologists but can be applied to almost all fields of study as a logical, rational problem-solving method.

By the end of this section, you will be able to:Identify the shared characteristics of the natural sciencesSummarize the steps of the scientific methodCompare inductive reasoning with deductive reasoningDescribe the goals of basic science and applied science

By the end of this section, you will be able to:Identify the shared characteristics of the natural sciencesSummarize the steps of the scientific methodCompare inductive reasoning with deductive reasoningDescribe the goals of basic science and applied science

Students learn a simple technique for quantifying the amount of photosynthesis that occurs in a given period of time, using a common water plant (Elodea). They can use this technique to compare the amounts of photosynthesis that occur under conditions of low and high light levels. Before they begin the experiment, however, students must come up with a well-worded hypothesis to be tested. After running the experiment, students pool their data to get a large sample size, determine the measures of central tendency of the class data, and then graph and interpret the results.

Few people are aware of how crucial the sense of smell is to identifying foods, or the adaptive value of being able to identify a food as being familiar and therefore safe to eat. In this lesson and activity, students conduct an experiment to determine whether or not the sense of smell is important to being able to recognize foods by taste. The teacher leads a discussion that allows students to explore why it might be adaptive for humans and other animals to be able to identify nutritious versus noxious foods. This is followed by a demonstration in which a volunteer tastes and identifies a familiar food, and then attempts to taste and identify a different familiar food while holding his or her nose and closing his or her eyes. Then, the class develops a hypothesis and a means to obtain quantitative results for an experiment to determine whether students can identify foods when the sense of smell has been eliminated.

Students will explore the steps in conducting scientific investigation in Agriculture and discuss safety precautions that should be followed in conducting agricultural research. Lesson plan from the New Mexico Animal, Plant, and Soil Science Lesson Plan Library.

Students learn about the amazing adaptations of the ptarmigan to the alpine tundra. They focus one adaptation, the feathered feet of the ptarmigan, and ask whether the feathers serve to only keep the feet warm or to also provide the bird with floatation capability. They create model ptarmigan feet, with and without feathers, and test the hypothesis on the function of the feathers. Ultimately, students make a claim about whether the feathers provide floatation and support this claim with their testing evidence.

In the first part of the activity, each student chews a piece of gum until it loses its sweetness, and then leaves the gum to dry for several days before weighing it to determine the amount of mass lost. This mass corresponds to the amount of sugar in the gum, and can be compared to the amount stated on the package label. In the second part of the activity, students work in groups to design and conduct new experiments based on questions of their own choosing. These questions arise naturally from observations during the first experiment, and from students' own experiences with and knowledge of the many varieties of chewing and bubble gums available.

Imagine trying to cut your hair without metal tools. How would you do it? Join JPPM's Educator Nate Salzman as he uses experimental archaeology to answer the question "How did Native Americans cut their hair before metal tools?" Use to support the Maryland Social Studies Framework for grades 3, 4, and High School. To support the grade 3 content topic "Cultural Change Over Time," have students compare the advantages/disadvantages of the results of this experiment and how they receive a hair cut; for grade 4 topic "Native Cultures," have students either hypothesize and research how Native American tribes who did not have access to shells may have cut their hair or respond to the prompt "why did European colonists use metal tools for cutting their hair while the Native Americans used shells? Would some hair styles be easier to cut with one type of tool than the other?"; finally for HS topic "Exploration, Colonization, and Global Interaction, have students respond to the prompt "with the introduction of metal tools, how might the role of 'barber' have changed within a Native American tribe? If you evaluate or use this resource, consider responding to this short (4 question) survey at bit.ly/3G6RxUa

The Experimental Project Lab in the Department of Aeronautics and Astronautics is a two-semester course sequence: 16.621 Experimental Projects I (this course) and 16.622 Experimental Projects II. This site offers material on 16.621. In the course, two-person teams initiate a project of their own conception and design in 16.621 and then complete it in 16.622. For many students, this is a first encounter with research standards and techniques. It is a complicated course that requires a lot of interaction and support and also access to facilities and materials, but it is rewarding for students to explore an hypothesis under the guidance of a faculty advisor.
This OCW site presents the building block materials of the course, which can provide only a profile of the course because the most important learning elements are the interactions between student team, faculty, project advisor, and shop staff and also between student team members. However, this site offers some of the preparation and guidance materials for students embarking on an experimental project. To emphasize the focus on communication skills, a set of study materials and examples of student work are provided.

The Experimental Project Lab in the Department of Aeronautics and Astronautics is a two-semester course sequence: 16.621 Experimental Projects I and 16.622 Experimental Projects II (this course). Students in 16.622 gain practical insight and improved understanding of engineering experimentation through design and execution of “project” experiments. Building upon work in course 16.621, students construct and test equipment, make systematic experimental measurements of phenomena, analyze data, and compare theoretical predictions with results. Deliverables comprise a written final project report and formal oral presentations. Instructions on oral presentations and multi-section reporting are given. Experimental Projects I and II provide a valuable link between theory (16.621) and practice (16.622).

Free printable graphic novel that uses animal behavior to teach kids about the scientific method in a fun, hands-on way. Free lesson plan also available.

This activity is designed to support a variety of STEM concepts: scientific method, making predictions, gathering and analyzing data, and developing conclusions based on experimentation. This activity draws on active student engagement, and is useful in many STEM content areas.