Ch 1 - The Nature of Science

What is Science? A. A way of learning about the natural world 1. Want to know why & how something occurred 2. To do this, one must ask questions B. Asking questions 1. Science can answer a lot of questions but it can’t answer things about art, politics, morality, right or wrong, good or bad or personal preferences

Possible Explanations 1 Possible Explanations 1. With science any answer is uncertain because people will never know everything about the world around them 2. With new knowledge they might realize that some old explanations no longer fit new information

Explanation still possible Modified New Info. Question Experiment Discarded Still Possible – solar system: learn about a new planet/solar system---doesn’t take away from what we know about existing planets Modified – solar system: made up of 9 planets—made up of 8 planets (w/o Pluto) cooking: still add parsley but also basil Discarded – solar system: Earth is not the center of solar system----Pluto is not a planet cooking: don’t cook at 400 for 30 min New Explanation – solar system: Sun is the center of the solar system----Pluto is a dwarf planet cooking: cook at 325 for 1 hour New explanation possible

Scientific Theories 1. Is an attempt to explain a pattern that is observed repeatedly in the natural world Ex: The Sun rises in the East and sets in the West as a result of the counterclockwise rotation of the Earth. 2. Theories are the best explanations but they can change 3. Theories explain why something happens

Scientific Laws 1. Is a rule that describes a pattern in nature Ex: The Sun rises in the East and sets in West 2. To become a law it must be observed repeatedly 3. A law does not attempt to explain why something happens, it just describes the pattern

B. Systems are found everywhere Systems in Science A. A system is a collection of structures, cycles and processes that relate and interact with each other Ex: solar system, body systems, ecosystems, life cycles, water cycle etc. B. Systems are found everywhere C. All systems are made up of other systems Ex: Human body system made of smaller systems; Our school system part of larger systems

Branches of Science A. There are 3 main categories or branches: 1. Life Science 2. Earth Science 3. Physical Science

Life Science 1. The study of living systems and the ways in which they interact 2. Biology, Zoology, Botany, Anatomy etc.

Earth Science 1. The study of Earth systems and the systems in space. It includes nonliving things such as rocks, soil, clouds, rivers, oceans, stars, weather, etc. 2. Astronomy, Geology, Meteorology etc.

Physical Science 1. The study of matter & energy a) Matter – anything that has mass and takes up space b) Energy – the ability to change matter 2. EVERYTHING (living and nonliving systems) is made of matter ex: plants, animals, water, air/ atmosphere, clouds

3. Physical science is divided into 2 general categories: 3. Physical science is divided into 2 general categories: a) Chemistry – the study of matter and the interactions of matter b) Physics – the study of energy and its ability to change matter

A. Jobs that are science related Careers A. Jobs that are science related 1. Medical – doctors, nurses, ultrasound & x-ray technicians, sports medicine, physical therapists 2. Research – chemists, physicists, biologists 3. Engineering B. Technology – practical use of science or applied science

1. State the problem/question Science in Action A. Scientists have a huge collection of skills that they use to solve problems B. Scientific Method 1. State the problem/question 2. Collect information/Research 3. Hypothesize 4. Experiment 5. Record Data 6. Draw a conclusion 7. Repeat

C. Infer – to draw a conclusion based on an observation

D. Experiments 1. Are means to test hypotheses 2. Controlled Experiment – a test where only one factor is changed at a time to observe how it affects another factor

3. Factors that can be changed in an experiment are called variables. a) Independent variable – the factor that is changed/ thing you are testing b) Dependent variable – a factor that changes as a result of the independent variable c) Constants – factors that are NOT changed in an experiment

E. Lab Safety. 1. The #1 rule: Think before you act. 2 E. Lab Safety 1. The #1 rule: Think before you act 2. Know the location of equipment 3. Have good safety habits *Draw and learn lab safety symbols – p.19

Models in Science A. A model is any representation of an object or an event used as a tool for understanding the natural world 1. Models help visualize something that is difficult to see ex: something that is too big, too small, no longer exists etc.

B. Types of Models. 1. Physical Models. a) can see & touch B. Types of Models 1. Physical Models a) can see & touch ex: pictures or 3-D, maps, globes b) shows how parts relate to one another c) used to show how things appear or react when an outside force acts on them

2. Computer Models. a) use software – can see but not touch 2. Computer Models a) use software – can see but not touch b) used for events too slow or too fast to actually see ex: weather models, plate tectonics etc. Weather.com - US map radar Rose Bloom Flowers blooming, Clouds & Water drop

3. Idea Models. a) concepts that describe how someone 3. Idea Models a) concepts that describe how someone thinks about something in the natural world ex: Einstein's theory of relativity E=mc2 Theory of Relativity: Under right conditions mass (matter) and energy can be interchangeable Small amount of mass X the speed of light (how fast energy moves) =/turns into a huge amount of energy (a walnut has enough energy stored to power a city) 1879-1955

C. Using Models. 1. Not all models used for scientific purposes. 2 C. Using Models 1. Not all models used for scientific purposes 2. Other uses: a) Communication – to relay information and ideas to people ex: globes, blueprints, recipes

b) Test predictions ex: wind tunnels to duplicate flight conditions

c) Save time, money & lives ex: crash test dummies

D. Evaluating Scientific Explanation. 1. Critical Thinking – combining D. Evaluating Scientific Explanation 1. Critical Thinking – combining knowledge that you already have with new facts that you are given in order to decide for yourself if you should agree with something

2. Data – the observations and information gathered in an experiment; it can be recorded in the form of a written description, table, chart or drawing a) must consider if the data is specific and exact ex: how many people were involved in a study – are exact #’s used?

b) scientists must be able to back up b) scientists must be able to back up their statements with specific data and it must be able to be repeated by other scientists 3. Good Notes – write down every observation because you can easily forget something in a few hours