Science As A Way of Knowing Chapter 1 Science As A Way of Knowing

Chapter 1 Science As A Way of Knowing By applying scientific methodology, biologists can find answers to questions that arise in the study of life.

1.1 What Is Science? 1. One goal of science is to provide natural explanations for events in the natural world.

2. Several features make science different from other human endeavors 2. Several features make science different from other human endeavors. a. science deals only with the natural world.

b. scientists collect and organize information in an b. scientists collect and organize information in an orderly way, looking for patterns and connections among events.

c. scientists propose explanations that are based on evidence, not belief. Then they test those explanations with more evidence.

3. Science also aims to use those explanations to understand patterns in nature and to make useful predictions about natural events.

Scientific knowledge helps us cure diseases, place satellites in orbit, and send instantaneous electronic communications.

Yet, despite all we know, much of nature remains a mystery Yet, despite all we know, much of nature remains a mystery. It is a mystery because science never stands still; almost every major scientific discovery raises more questions than it answers.

4. scientific methodology – the general style of scientific investigation

5. Scientific methodology involves observing and asking questions, making inferences and forming hypotheses, conducting controlled experiments, collecting and analyzing data, and drawing conclusions.

6. science (5) - an organized way of gathering and analyzing evidence about the natural world.

7. observation (6) - the act of noticing and describing events or processes in a careful, orderly way.

8. inference (7) - logical interpretation based on what scientists already know

9. Testing a scientific hypothesis often involves designing an experiment that keeps track of various factors that can change, or variables.

10. hypothesis (7) - scientific explanation for a set of observations that can be tested in ways that support or reject it

11. Variable – factor that can change in an experiment Examples of variables include temperature, light, time, and availability of nutrients.

12. Whenever possible, a hypothesis should be tested by an experiment in which only one variable is changed. All other variables should be kept unchanged, or controlled.

13. controlled experiment (7) - experiment in which only one variable is changed

14. Variables are controlled in experiments because if several variables are changed in the experiment, researchers can’t easily tell which variable is responsible for any results they observe.

15. independent variable (7) - factor in a controlled experiment that is deliberately changed; also called manipulated variable 16. dependent variable (7) - variable that is observed and that changes in response to the independent variable; also called the responding variable 17. control group (7) - group in an experiment that is exposed to the same conditions as the experimental group except for one independent variable

18. Typically, an experiment is divided into control and experimental groups.

19. data (8) – evidence; information gathered from observations

20. Quantitative data - information about quantities; that is, information that can be measured and written down with numbers. 21. Qualitative data – information about qualities; information that can't actually be measured. Use descriptions

22. Scientists choose appropriate tools for collecting and analyzing data. 23. Researchers must be careful to avoid errors in data collection and analysis.

Data analysis and sample size must be chosen carefully. 24 Data analysis and sample size must be chosen carefully. 24. The larger the sample size, the more reliably researchers can analyze that variation and evaluate the differences between experimental and control groups.

25. Scientists use experimental data as evidence to support, refute, or revise the hypothesis being tested, and to draw a valid conclusion.

26. Sometimes hypotheses are not fully supported or refuted by one set of experiments and the original hypothesis is reevaluated and revised; new predictions are made, and new experiments are designed.

1.2 Science in Context Curiosity, skepticism, open-mindedness, and creativity help scientists generate new ideas.

Scientists share their findings with the scientific community by publishing articles that have undergone peer review

2. Peer review - scientists publish articles about experiments to be reviewed by anonymous, independent experts.

3. Publishing peer-reviewed articles in scientific journals allows researchers to share ideas and to test and evaluate each other’s work.

4. In science, the word theory applies to a well tested explanation that unifies a broad range of observations and hypotheses and that enables scientists to make accurate predictions about new situations.

5. theory (13) - well-tested explanation that unifies a broad range of observations and hypotheses, and enables scientists to make accurate predictions about new situations

6. No theory is considered absolute truth 6. No theory is considered absolute truth. Science is always changing; as new evidence is uncovered, a theory may be revised or replaced by a more useful explanation.

Science can help with many problems in our world but because they involve the places we live, our economy, laws and moral principles, other things must be considered besides pure science.

Using science involves understanding its context in society and its limitations. 7. When scientists explain “why” something happens, their explanation involves only natural phenomena. Pure science does not include ethical or moral viewpoints. 8. Science can tell us how technology and scientific knowledge can be applied but not whether it should be applied in particular ways.

9. The way that science is applied in society can be affected by bias 9. The way that science is applied in society can be affected by bias. 10. bias (14) - particular preference or point of view that is personal, rather than scientific

11. Examples of biases include personal taste, preferences for someone or something, and societal standards of beauty. 12. Scientists should not demonstrate bias in their scientific writings.

1.3 Studying Life biology (17) - scientific study of life

2. All living things share some of the following characteristics:

b. based on a universal genetic code called DNA a. made up of units called cells, b. based on a universal genetic code called DNA

c. obtain and use materials and energy,

d. grow and develop,

e. reproduce,

f. respond to their environment, (response to stimulus)

g. maintain a stable internal environment, (homeostasis)

h. and change over time (evolution)

3. All organisms store the complex information they need to live, grow, and reproduce in a genetic code written in a molecule called DNA. 4. DNA (18) – molecule containing genetic code for an organism

5. Every organism has a particular pattern of growth and development.

6. Organisms detect and respond to stimuli from their environment.. 7. stimulus (18) - signal to which an organism responds

8. All organisms reproduce, which means that they produce new similar organisms.

9. In sexual reproduction, cells from two parents unite to form the first cell of a new organism. 10. asexual reproduction (19) - process of reproduction involving a single parent that results in offspring that are genetically identical to the parent 11. sexual reproduction (19) - type of reproduction in which cells from two parents unite to form the first cell of a new organism

12. All organisms need to keep their internal environment relatively stable, even when external conditions change dramatically. This condition is called homeostasis.

13. homeostasis (19) - relatively constant internal physical and chemical conditions that organisms maintain

14. All organisms must take in materials and energy to grow, develop, and reproduce.

15. metabolism - The combination of chemical reactions through which an organism builds up or breaks down materials.

16. The study of biology revolves around several interlocking big ideas: a. the cellular basis of life; b. information and heredity; c. matter and energy; d. growth, development, and reproduction; e. homeostasis; f. evolution; g. structure and function; h. unity and diversity of life; i. interdependence in nature; j. and science as a way of knowing.

17. Living things are made of cells 17. Living things are made of cells. Unicellular – single cells; multicellular – many cells

18. The need for matter and energy link all living things on Earth in a web of interdependent relationships.

19. For most organisms, any breakdown of homeostasis may have serious or even fatal consequences.

20. Although life takes an almost unbelievable variety of forms, all living things are fundamentally similar at the molecular level. 21. All organisms are composed of a common set of carbon-based molecules, store information in a common genetic code, and use proteins to build their structures and carry out their functions.

22. All forms of life on Earth are connected into a biosphere, which literally means “living planet.” Within the biosphere, organisms are linked to one another and to the land, water, and air around them.

23. biosphere (21) - part of Earth in which life exists including land, water, and air or atmosphere

24. Biology includes many overlapping fields that use different tools to study life from the level of molecules to the entire planet. 25. Most scientists use the metric system when collecting data and performing experiments.