The Nature of ScienceSection 1: The Methods of Science

Learning GoalsIdentify the steps that scientists often use to solve problems.

Describe why scientists use variables.

Compare and contrast science and technology.

ScienceScience studies natural

patterns.Science is classified into three

main categories: life science, Earth science, and

physical science.

ScienceScience explains the natural

world; explanations can change over time. Ancient Greek philosophers

thought that everything was composed of five basic elements: ▪ earth, air, fire, water, and aether

ScienceScientists investigate nature by

observation, experimentation, or modeling.

Scientific Method Scientific method: organized

set of investigation procedures1. State a problem.

Scientific Method2. Gather information

Scientific Method3. Form a hypothesis based on knowledge and

observation. Hypothesis: TESTABLE statement that is

used to set up an experiment! 15 year old males are taller than 15 year old females

The Steelers are better than the Ravens Dinosaurs were blue in color

Bacteria do not need oxygen to survive

Scientific Method4. An experiment with variables is a

common way to test a hypothesis. Experiment: a test of the effect of

one variable on another using controlled conditions.

Variable: a quantity that can have more than a single value.

Scientific Methoda) An independent variable is the

variable changed in an experiment to see the effect.

b) A dependent variable is the variable that changes as a result of the independent variable.

Scientific Method

Scientific Methodc) A variable that does not change

when other variables change is a constant.

d) A control is the standard to which test results can be compared.

Scientific Method5. Analyze data from an experiment

or investigation.Plant Amount of Water Amount of

SunHeight after two weeks

A 4 oz. every three days 6 hr/day 18cm

B 4 oz. every three days 0 hr/day 6cm

Scientific Method6. Form a conclusion based on the

data.

Scientific Method7. Reduce bias by keeping accurate

records, using measurable data, and repeating the experiment.

Bias: occurs when what the scientist expects changes how the results are viewed.

ModelsModel: represents

an idea, event, or object to help people better understand it. All models have

limitations.

Theory versus LawTheory: an explanation based on

MANY observations and investigations

Scientific law: is a statement about something in nature that always seems to be true.

Theory versus LawA theory can never become a law! Instead theories are used to explain laws.

Limits of ScienceScience deals with the natural world; questions of value or emotion cannot be answered.

TechnologyTechnology: applied science

helping people

Section ReviewExplain why a control is needed in

a valid experiment.What is the dependent variable in

an experiment that shows how the volume of gas changes with changes in temperature?