The Nature of Science

What is Science?

*Science-a way of learning more about the natural world. *Science comes from the Latin word scire which means “to know” *Scientists want to know: -How? -Why? -When?

Who are some scientists that are around you? Meteorologists Ecologists Volcanologists Chemists Science Teachers Yourself

The Branches of Science Life Science-the study of living systems and the ways they interact. They study living organisms, where they live and how they interact. Earth Science-the study of Earth and the systems in space. This includes the study of nonliving things such as rock, soil, clouds, rivers, oceans, planets, stars, etc. Physical Science-The study of matter and energy. Includes living and nonliving systems.

Science Depends on communication, agreement, and disagreement among scientists. It is composed of hypotheses, theories, and laws.

Hypothesis Reasonable guess that can be tested and is based on what is known and what is observed.

Scientific Theory- a possible explanation for repeatedly observed patterns in nature. Best explanation found so far, but theories can change over time. (usually with advancements in technology)

Human Cell

1. Hypothesis versus Theory Established idea Factual Experiments Data Hypothesis: Educated guess If I do….then I expect…… correct or incorrect

Scientific Law a rule that describes a pattern in nature but does not try to explain why something happens. Law does not explain why gravity exists or how it works. Helps in prediction Will not usually change but can if technology proves it incorrect. (RARE)

Law of Conservation of Mass

Law of Conservation of Energy Energy cannot be created or destroyed!

Scientific Method 6 Steps Is a systematic search for information by observation and experimentation. Series of Steps used to solve or answer a question.

Form a Question Develop a Hypothesis Propose and Perform an Experiment

Compare Results Form Conclusion to see if hypothesis is correct or incorrect If incorrect, form new hypothesis and repeat

Observation  the process of obtaining information by using the senses. (Sight, Smell, Taste, Hear, Touch) Data  pieces of information acquired through observation or experimentation. (TCAP Scores, Tests Scores, etc.) -- Watch for incorrect Data (Human Error, Faulty Equipment, etc.)

Bias Bias: Prejudice in favor of or against one thing, person, or group compared with another, usually in a way considered to be unfair. All experiments need to be free of Bias, in order to give accurate results.

Using Models to Visualize A model is any representation of an object or an event used as a tool for understanding the natural world.

Types of Models Physical-models that can be seen and touched. Ex.: Globe, cell , solar system Computer-use software; you can view but cannot touch. Ex.: Weather forecasting, earthquake predictions Idea-describe how someone thinks about something in the natural world Ex.: Einstein’s E=mc2, these models cannot be physically built

Graphs Bar Graph --- a graph consisting of vertical or horizontal bars whose lengths are proportional to amounts or quantities

Graphs Line Graph --- a diagram of lines made by connected data points which represent successive changes in the value of a variable quantity or quantities

Graphs Pie Graph --- circular graph used in statistics that is divided by radii like a pie to depict the proportion of the variables (Always 100%)

Limitations Not Perfect Are a representation Limited by existing knowledge and information Can be in a constant state of change Can be misleading if not properly viewed

Parts of a Lab Experiment 3 Different Kinds of Variables: Control Independent Variable Dependent Variable

Control A. Control  What you keep Constant within the experiment you are doing (It will Not Change)

Independent Variable -- What you deliberately alter in the Experiment B. Independent Variable  Is a Variable you can Control (It Changes) -- What you deliberately alter in the Experiment (Example: Time)

Dependent Variable C. Dependent Variable  Is the Variable you can Observe -- This is what the investigator Measures, Counts, or Records

Independent (input) variable This is the thing that you decide to change. Example 1 Investigating how a weight affects the length of an elastic band. You decide the weight to apply, so: Weight is the independent variable.

Dependent (outcome) variable This is the variable that changes as a result. It is the variable that you measure. Example 1 Investigating how a weight affects the length of an elastic band. You measure the resulting length of the elastic band, so: Length is the dependent variable.

Control variables These are all the variables that must not change, to make sure it is a fair test. Example 1 Investigating how a weight affects the length of an elastic band. You must use the same elastic band all the time, and the same scale etc, so it is a fair test.

same elastic band, same scale, etc, so it is a fair test. In Summary Example 1 The independent variable is ? weight The dependent variable is ? length of the elastic The control variables are ? same elastic band, same scale, etc, so it is a fair test.

Independent (input) variable This is the thing that you decide to change. Example 2 Investigating how the rate of cooling of a beaker depends on the initial temperature. You decide the initial temperature, so: initial temperature is the independent variable.

Dependent (outcome) variable This is the variable that changes as a result. It is the variable that you measure. Example 2 Investigating how the rate of cooling of a beaker depends on the initial temperature. You measure the temperature every minute as it cools, so: temperature is the dependent variable.

Control variables These are all the variables that must not change, to make sure it is a fair test. Example 2 Investigating how the rate of cooling of a beaker depends on the initial temperature. You must use the same beaker, with the same amount of water, in the same position in the room, at the same room temperature, so it is a fair test.

temperature as it cools In Summary Example 2 The independent variable is ? initial temperature The dependent variable is ? temperature as it cools The control variables are ? the same beaker, with the same amount of water, in the same position in the room, at the same room temperature, so it is a fair test.

Example 3 Experiment: Do men and women absorb Vitamin D differently? What is the Control, Independent Variable, and Dependent Variable?

Control: Men and Women Independent Variable: Vitamin D Dependent Variable: Rate of Absorption

Example 4 How much moisture will it take for Bread to Mold? What is the Control, Independent Variable, and Dependent Variable?

Control: Bread Independent Variable: Amount of (moisture) water you use Dependent Variable: When Mold started to Grow

Example 5 Does the brightness of light have any effect on a Moth being attracted to light? What is the Control, Independent Variable, and Dependent Variable?

Control: Moth Independent Variable: Brightness of Light Dependent Variable: How Moth reacts to different levels of Light

Example 6 Will Sunlight effect Plant Growth? What is the Control, Independent Variable, and Dependent Variable?

Control: Plants Independent Variable: Different amounts of Sunlight Dependent Variable: Plant Growth

Example 7 Does a new drug have any effect on Cancer Patients? What is the Control, Independent Variable, and Dependent Variable?

Control: Cancer Patients Independent Variable: New Drug and Sugar Pill (Placebo) Dependent Variable: Difference in Mortality Rate

Science and Engineering

What is the one thing that limits scientific discovery? Technology- The practical use of science or applied science.

Technology Technology refers to the products and processes that are designed to meet our needs.

Technology and Society Technology has many great advantages but there is a dark side. Intended benefits- uses or results that engineers purposely include in their design of products. (Cell phones keeping you in touch with others. Unintended Consequences-uses or results that engineers do not purposely include in the design of products. (Cell phone towers, cyber-bullying, etc.)

Technology has intended benefits and unintended consequences. Benefits -- World Wide Communication, Better Medicine, Faster Travel, More Food, Cleaner Energy, etc…..

Sometimes Technology has Unintended Consequences Internet Medication Cars

Engineering  the application of scientific, economic, social, and practical knowledge in order to design, build, maintain, and improve structures, machines, devices, systems, materials and processes. This may include mechanical, electrical, chemical, bioengineering, etc. Has a major impact on our daily lives.

Engineering Design Process The process of creating new technology Identify and Research a need. Develop possible solutions Make a prototype (a test model) Test and evaluate the prototype (Cost-Benefit analysis) 5. Modify and retest.

Engineering Design Process Prototype-a representation designed to show the structure or working of an object. Goal --- just to see it if could work Cost-benefit analysis- the process of determining whether the cost of doing something is worth the benefit it provides.

Thomas Edison Inventor: Light Bulb, Video Camera, Phonograph “I have not Failed. I’ve just found 10,000 ways that won’t work.” Inventor: Light Bulb, Video Camera, Phonograph

Ford F150 History 1917 1948 2014 1975

Evolution of Helicopter Leonardo Da Vinci 1493

Today

Evolution of Helicopter Leonardo Da Vinci 1487

Mercedes SCL 600 Series

Communication

Music

Calculator

Bioengineering Adaptive/Assisitive

Bioengineering Applying the engineering design process to living things.

Assistive Bioengineering --- Helps living organisms without changing them It does not change the organism (Not Permanent) It also includes new technology.

Crutches

Eyeglasses or Contacts

Hearing Aid

Prosthetic Leg

Other Assistive Technologies Cast Knee Brace Band Aid Wheelchair Stitches

Adaptive Bioengineering --- Helps living organisms by changing them It does change the organism! (It is Permanent) It is new forms of old technology

Bioengineered Corn and Biofuel Scientists have inserted into corn a gene from the bacterium Bacillus thurigiensis, usually referred to as BT. The gene makes a protein lethal to certain caterpillars that destroy corn plants. This form of insect control has two advantages: It reduces the need for chemical pesticides, and the BT protein, which is present in the plant in very low concentrations, has no effect on humans. http://www.pbs.org/wgbh/harvest/

Luminescent Tobacco

Cochlear Implant

Cochlear Implant

The Modular Prosthetic Limb (MPL) is a brain-controlled prosthetic that has nearly as much dexterity as a natural limb, and allows independent movement of fingers.

Lasik Eye Surgery

Braces

Artificial Heart

Pacemaker

Knee Replacement

Hip Replacement

Tools of the Trade Graduated Cylinder or Beaker-measures volume Thermometer-measure temperature Triple-Beam Balance-measures mass Spring Scale-measures force (uses Gravity) Stopwatch-measures time Meter Stick-measures length

United States Measurement Length --- (Inches, Foot/Feet, Miles) Volume --- (Ounce, Quart, Gallon) Mass --- (Pounds) Temperature --- (Fahrenheit)

SI Measurement SI-The International System of Units (This is the metric system) -- (advantage) helps all scientists share and compare their observations and data.

Length --- (Meter) Volume --- (Liter) Mass --- (Gram) Temperature --- (Kelvin or Celsius)