scientific thinking body of knowledge - nature of science big idea 1 – the practice of science big...
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Scientific Thinking
Body Of Knowledge - Nature of ScienceBig Idea 1 – The Practice of ScienceBig Idea 2 – The Characteristics of Scientific KnowledgeBig Idea 3 – The Role of Theories, Laws, Hypotheses, and Models
SC.8.N.2.2 – Discuss what characterizes science and its methods
Science is a way of understanding the natural world around us. It is based upon the idea that our senses, and extensions of our senses through instrumentation/technology, give us accurate information about the natural world.
Scientists ask, “What is there? How does it work? How did it come to be this way?
The joy of science is in the freedom to explore and wonder
Science relies on evidence and creativity
Science explanations are evaluated by testing and using evidence. Explanations that don’t fit evidence are rejected or modified and tested again.
Science claims are subject to peer review and replication. Scientists attempt to identify alternate explanations to get closest to the truth.
There is NO one “Scientific Method”! Scientists continually make observations, question, and form multiple hypotheses.
http://evolution.berkeley.edu/evosite/nature/IIprocess3.shtml
Science never “proves.” Hypotheses are either “supported” or “not supported” by the data collected.
SC.6.N.1.5 – Recognize that
science involves creativity,
not just in designing
experiments, but also in
creating explanations that fit
evidence
Dinosaur Extinction Hypotheses:Asteroid? Volcanism?Climate Change?
SC.8.N.1.5 – Analyze the methods used to develop a scientific explanation as seen in different fields of sciencePhysicists
Biologi
st
Volcanologist
Geologists
Chemists
SC.7.N.1.6 – Explain that empirical evidence is the cumulative body of observations of a natural phenomenon (event) on which scientific explanations are based
SC.7.N.1.7 – Explain that scientific knowledge is the result of a great deal of debate and confirmation within the science community
Science
Conferences
SC.8.N.1.6 – Understand that scientific investigations involve the collection of relevant empirical evidence, the use of logical reasoning, and the application of imagination in devising hypotheses, predictions, explanations, and models to make sense of collected evidence
SC.6.N.3.1 – Recognize and explain that a scientific theory is a well supported and widely accepted explanation of nature and is not simply a claim posed by an individual.
The Theory of Plate TectonicsEvidence – Sea Floor Spreading, Distribution of earthquakes and volcanoes, Fossils
Claim – Volcanoes erupt in Hawaii because of Pele, the goddess of fire
SC.6.N.3.2 – Recognize and explain that a scientific law is a description of a specific relationship under given conditions in the natural world (different from societal laws).
Newton’s Laws of Motion
SC.6.N.3.3 – Give several examples of scientific laws
Newton’s Laws of Motion
Universal Law of Gravitation
Law of Conservation of Energy
Law of Conservation of Mass
SC.7.N.3.1 – Recognize and explain the difference between theories and laws and give several examples of scientific theories and the evidence that supports them
THEORY•Explanation based upon evidence•Verified multiple times•Can be used to make predictions
LAW•A statement that describes an action or set of actions•Can be expressed as a mathematical equation•Simple, true, universal
•Theories explain WHY
something happens •Laws describe WHAT happens
Theory Example – The Theory of Biological EvolutionAll life on Earth shares a common ancestor. There is “decent with modification.”
Evidence – Fossil Record, Genetic Studies, Radiometric Dating, Stratigraphy
The horse’s foot adapted to a changing climate
http://www.sepa.duq.edu/darwin/education-tools-horseFeet_new.shtml
SC.6.N.3.4 – Identify the role of models.
Model – a representation of an object, process, system, or event that is
similar to the original object or idea role – models help scientists better understand objects/ideas; allow hands-on contact with matter that is too small, too large, too far away, too dangerous, or too expensive to build
SC.7.N.3.2 – Identify the benefits and limitations of the use of scientific models
Benefits•Used to study matter that is too large, too small, too far away, too dangerous, or too expensive to study directly•Models can be physical, mathematical, computer simulations, or conceptual•Can be used to make predictions
Limitations•May lack details•May not be composed of the original material (model of the Sun)•May not be able to demonstrate every aspect of the system
SC.6.N.2.2 – Explain that scientific knowledge is durable because it is open to change as new evidence or interpretations are encounteredSC.8.N.3.2 – Explain why theories may be modified but are rarely discarded
Miasma - Before the 1800s, it was thought that diseases were caused by miasma, a poisonous vapor in the air filled with particles of decaying matter!
Germ Theory (1870s) – specific microorganisms are the causes of specific diseases
Louis Pasteur demonstrated that microbes decomposedmeat and heat killsbacteria
Robert Kochdemonstrated that specific diseases werecaused by specific germs
SC.7.N.1.2 – Differentiate replication (by others) from repetition (multiple trials)
Trial Numb
er
Height after 5 Days (cm)
1 30
2 31
3 30
4 30.5
5 31
AVE 30.5
Dr. Square copied Dr. Groovy’s procedure and got similar results! The plants grew an average of 30 cm in 5 days!
If scientific explanations are replicable, they are more valid and reliable.
Table 1: Plant Growth with TurboGro by Trial
SC.6.N.1.2 – Explain why scientific explanations should be replicable
SC.8.N.1.3 – Use phrases such as “results support” or “fail to support” in science, understanding that science does not offer conclusive “proof” of a knowledge claim
HypothesisIf Turritella snail fossils are compared for height and number/location of predation drill holes, then there will be an escape size where the holes are absent, because the predators in the community would no longer be large enough to feed on the snails.DiscussionIn the study area, predation drill holes are absent on Turritella over 6 cm. The results support the hypothesis. The researcher infers that once Turritella grew to 6 cm in length, it escaped predation.
EXAMPLE
There is NO conclusive proof of this claim, as this is one study conducted in one particular study area.
SC.8.N.1.4 – Explain how hypotheses are valuable if they lead to further investigations, even if they turn out not to be supported by the data
Studies that analyze the strengths and weaknesses of alternative explanations are valuable.
They encourage others to more thoroughly examine the ideas and evidence and to develop new ways to test the ideas.
SC.6.N.1.3 – Explain the difference between an experiment and other types of scientific investigation, and explain the relative benefits and limitations of each SC.7.N.1.3 – Distinguish between an experiment and other forms of scientific investigation and explain that not all scientific knowledge is derived from experimentation
Experiment – involves identification and control of variables Independent variable/test variable/manipulated
variable Dependent variable/outcome variable/responding
variable Controlled variables
Field Study – observe a natural habitat without manipulating variables
Simulation – imitating a real situation or process
SC.7.N.1.4 – Identify test variables (independent variables) and outcome variables (dependent variables) in an experiment
Independent Variable (Test
Variable):the amount of light per day
Dependent Variable (Outcome
Variable):plant growth measured in cm