Methods of Science Chapter 1 Section 3

Science is a process based on inquiry that develops explanations. Main Idea Science is a process based on inquiry that develops explanations.

What are the differences between an observation and an inference? Thinking Questions What are the differences between an observation and an inference? What are the differences among a control, independent variable, and dependent variable? What are the scientific methods a biologist uses for research? Why are the metric system and SI important? Copyright © McGraw-Hill Education

Scientific Inquiry Science- a body of knowledge based on the study of the natural world Theory- an explanation of a natural phenomenon supported by many observations and experiments Scientific Law- describes relationships under certain conditions in nature Peer Review- a process by which the procedures and results of an experiment are evaluated by other scientists Ethics- a set of moral principles or values Forensics- the field of study that applies science to matters of legal interest and other areas such as archaeology

Ask a Question Scientific inquiry begins with observation. Scientific inquiry involves asking questions and processing information from a variety of reliable sources. Scientific Inquiry

Form a Hypothesis Scientific Inquiry A hypothesis is a testable explanation of a situation. When a hypothesis is supported by data from multiple investigations, the hypothesis is usually considered valid and is accepted by the scientific community. If the hypothesis is not supported by scientific investigations, the hypothesis is revised, and additional investigations are conducted . Scientific Inquiry

Scientific Methods Scientific Inquiry Scientific inquiry begins with observation, a direct method of gathering information in an orderly way. The process of combining what you know with what you have learned to draw logical conclusions is called inferring; the conclusions themselves are called inferences. The methods scientists use to gather data and answer questions are referred to as scientific methods. Scientific Inquiry

Collect the Data Controlled experiments Scientific Methods When a scientist conducts an experiment, they investigate a phenomenon in a controlled setting to test a hypothesis. The control group in an experiment is the group used for comparison. An experimental group is a group exposed to the factor being tested. Scientific Methods

Collect the Data Scientific Methods Experimental design During a controlled experiment, only one factor can change at a time. Independent variable —the tested factor that might affect the outcome of the experiment Dependent variable —results from or depends on changes to the independent variable. Constant —a factor that remains fixed during an experiment while the independent and dependent variables change. Scientific Methods

Collect the Data Data gathering Scientific Methods As scientists test their hypotheses, they gather data– information gained from observations. Quantitative data can be collected as numbers, such as measurements of time, temperature, length, mass, etc. Qualitative data are descriptions of what our senses detect. Data is organized in notebooks and tables Scientific Methods

Collect the Data Scientific Methods Investigations Not all scientific inquiry is based on controlled experiments Investigations rely on observation and collection of data rather than manipulating variables Metric system The metric system uses units with divisions that are powers of ten. SI units (International System of Units) are commonly used in science for consistency and ease of communication. Scientific Methods

Analyze the Data Scientific Methods After data collection, scientists use analyses to ask questions, such as “Has my hypothesis been supported?” or, “Is more data needed?” Patterns in data can be displayed in tables and graphs. Data analysis determines if the hypothesis is supported or rejected. Scientific Methods

Report Conclusions Scientific Methods Before a scientist can publish their findings, it must be peer- reviewed. If the reviewers agree on the merit of a paper, it is published in a scientific journal. Other scientists use published papers to evaluate and develop their own research. Scientific Methods

Define the Problem – Ask a Question/Make Observation Steps to the Scientific Method Define the Problem – Ask a Question/Make Observation Form a Hypothesis Design a Controlled Experiment Collect Data Analyze Data Draw Conclusions Communicate Results

Review Essential Questions Vocabulary What are the differences between an observation and an inference? What are the differences among a control, independent variable, and dependent variable? What are the scientific methods a biologist uses for research? Why are the metric system and SI important? Vocabulary observation inference scientific method experiment control group experimental group independent variable dependent variable constant data metric system SI Copyright © McGraw-Hill Education Methods of Science