Post on 27-Dec-2015
… From the Beginning
Copyright © Houghton Mifflin Harcourt Publishing Company
What is science?
• Science is the study of the natural world.
• Scientists study many different things, living and nonliving, from the deepest parts of the ocean to the objects in outer space.
• The natural sciences are divided into three areas: biology or life science, geology or Earth science, and physics or physical science. Chemistry is often included in physical science.
Unit 1 Lesson 3 Scientific Knowledge
What is science?
• Biology, or life science, is the study of living things.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What is science?
• Geology, or Earth science, is the study of Earth and the processes that shape Earth.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What is science?
• Physical science is the study of nonliving matter and energy.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What does science tell us?
• Scientific knowledge is constantly changing.
• Many things that people consider scientific “facts” are actually the most widely accepted explanations.
• What we learn in science are what most scientists agree are the best explanations about how things happen. They are theories scientists have about the world.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What does science tell us?
• A scientific theory is an explanation supported by a large amount of evidence.
• Theories are what most scientists agree to be the best explanations based upon what we now know.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
Not a Theory—It’s a Law!
Copyright © Houghton Mifflin Harcourt Publishing Company
How do scientific theories differ from laws?
• The words law and theory have specific meanings in science.
• A scientific law is a description of a specific relationship under given conditions in the natural world.
• Scientific laws describe the way the world works. They hold anywhere in the universe.
Unit 1 Lesson 3 Scientific Knowledge
What does Boyle’s Law describe?
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
• Boyle’s law describes the relationship between the volume and pressure of a gas that is kept at a constant temperature.
• Boyle’s law states that at a constant temperature, when the pressure of a gas is increased, its volume decreases. When the pressure of a gas decreases at a constant temperature, its volume increases.
What does Boyle’s Law describe?
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
How can Boyle’s Law be graphed?
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
A graph for Boyle’s Law shows that a pressure of a gas varies inversely with its volume at constant temperature (curved line)
How do scientific theories differ from laws?
• A scientific theory is a well-supported explanation of nature.
• Scientific theories are supported by many pieces of evidence.
• Theories help us understand and explain the laws we observe.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What is the Cell Theory?
• The cell theory states that living things are made up of cells that perform the basic functions of life.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
What’s Your Evidence?
Copyright © Houghton Mifflin Harcourt Publishing Company
Where do scientists get their evidence?
• Scientists are curious. They look at everything going on around them, ask questions, and collect information to answer these questions.
• Scientific knowledge is based on empirical evidence.
• Empirical evidence is all the measurements and data scientists gather in support of a scientific explanation.
Unit 1 Lesson 3 Scientific Knowledge
Where do scientists get their evidence?
• Scientists gather evidence in many places. Some do fieldwork, and others do laboratory work.
• Fieldwork is work done outdoors or where conditions cannot be controlled.
• Fieldwork gives scientists the opportunity to collect data in an original setting. Biologists and geologists do fieldwork.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
Where do scientists get their evidence?
• In a laboratory, scientists have the opportunity to collect data in a controlled environment.
• Most experiments are conducted in laboratories. In an experiment, scientists try to see what happens under certain conditions.
• Laboratories come in many varieties. They can be in the ocean or in the sky.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge
The Debate Continues
Copyright © Houghton Mifflin Harcourt Publishing Company
How do scientific ideas change?
• Scientific knowledge is what scientists think are the most-likely explanations for what we see. Over time, these explanations can change.
• Scientific ideas and explanations change when new evidence is found or when someone gives a better explanation of the old evidence.
Unit 1 Lesson 3 Scientific Knowledge
The Debate Continues
Copyright © Houghton Mifflin Harcourt Publishing Company
How has the model of the atom changed?
• The theory of atoms is a good example of how new evidence can modify an established theory.
Unit 1 Lesson 3 Scientific Knowledge
How do scientific ideas change?
• Scientists collaborate and share ideas. Often, many brains are better than one when solving a puzzle.
• Scientists regularly gather at meetings to discuss and debate ideas. Many ideas are not accepted at first.
• This rigorous evaluation ensures that scientific knowledge is solidly supported.
Copyright © Houghton Mifflin Harcourt Publishing Company
Unit 1 Lesson 3 Scientific Knowledge