This chapter explains how scientists think and how they "do" science. It describes how scientific theories develop and how scientists investigate questions to advance scientific knowledge. The chapter also explains how science may be misused and how and why human subjects are protected in scientific research.
- 1.1: Case Study - Why Should You Learn About Science?
- Samantha and Dave are expecting their first child. They are excited for the baby to arrive, but they are nervous as well. Will the baby be healthy?
- 1.2: What Is Science?
- You may think of science as a large and detailed body of knowledge, but science is actually more of a process than a set of facts. The real focus of science is the accumulation and revision of scientific knowledge. Science is a special way of gaining knowledge that relies on evidence and logic. Evidence is used to continuously test ideas. Through time, with repeated evidence gathering and testing, scientific knowledge advances.
- 1.3: The Nature of Science
- Science is a distinctive way of gaining knowledge about the natural world that starts with a question and then tries to answer the question with evidence and logic. Science is an exciting exploration of all the whys and hows that any curious person might have about the world. You can be part of that exploration. Besides your curiosity, all you need is a basic understanding of how scientists think and how science is done. In this concept, you'll learn how to think like a scientist.
- 1.4: Theories in Science
- A scientific theory is a broad explanation of events that is widely accepted by the scientific community. To become a theory, an explanation must be strongly supported by a great deal of evidence. People commonly use the word theory to describe a guess or hunch about how or why something happens. For example, you might say, "I think a woodchuck dug this hole in the ground, but it's just a theory." Using the word theory in this way is different from the way it is used in science.
- 1.5: Scientific Investigations
- Science is more about doing than knowing. Scientists are always trying to learn more and gain a better understanding of the natural world. There are basic methods of gaining knowledge that is common to all of science. At the heart of science is the scientific investigation. A scientific investigation is a plan for asking questions and testing possible answers in order to advance scientific knowledge.
- 1.6: Scientific Experiments
- An experiment is a special type of scientific investigation that is performed under controlled conditions. Like all investigations, an experiment generates evidence to test a hypothesis. But unlike some other types of investigations, an experiment involves manipulating some factor in a system in order to see how it affects the outcome. Ideally, experiments also involve controlling as many other factors as possible in order to isolate the cause of the experimental results.
- 1.7: Nonexperimental Scientific Investigations
- Many questions in human biology are investigated with observational as opposed to experimental studies. An observational study measures characteristics in a sample but does not attempt to manipulate variables of interest. A simple example of an observational study is a political poll. A sample of adults might be asked how old they are and which of two candidates they favor. The study provides a snapshot in time of potential voters' opinions and how they differ by age of the respondent.
- 1.8: Case Study Shot Conclusion and Chapter Summary
- New mother Samantha left her pediatrician’s office still unsure whether to vaccinate baby James. Dr. Rodriguez gave her a list of reputable sources where she could look up information about the safety of vaccines for herself, such as the Centers for Disease Control and Prevention (CDC).
Thumbnail: This image describes the Scientific Method as a cyclic/iterative process of continuous improvement. Image used with permission (Public Domain).