SCIENCE The goal of science is to understand the world around us. This involves curiosity. Asking questions is a start:
The Goals of Science • to investigate and understand nature • to explain events in nature • to use those explanations to make useful predictions
Understanding Fossil Butte • 50 million year old fish found at the top of Fossil Butte in Wyoming • Pacific Ocean over 1000 km away • How did they get there???
Before starting an experiment you can form an inference. Inference is the ability to use the information you have already obtained to help you form a hypothesis. • For example: Guess what five items are in the shoebox. Use your senses.
Observation between you an your partner may vary. It can be unreliable. • For example: If there were a car accident with 10 witnesses, chances are not all will agree on what happened. • Do demonstration.
Observation • Based on five senses: sight, hearing, taste, smell, touch • Quantitative – numerical • Ex- how many, how big, how fast • Qualitative – descriptive • Ex – color, texture, smell, behavior
If an experiment is done enough times it may become worthy of becoming a theory. A theory is a powerful, time tested concept that make useful and predictable predictions about the natural world. • Example: The Big Bang Theory
A Theory in Science • A very well supported hypothesis • When a hypothesis has been verified many times by different scientists, it becomes a theory • Redi’s, Spallanzani’s, and Pasteur’s experiments led to the theory of biogenesis (life comes from life) • Theories explain phenomena in nature
Spontaneous Generation • In the past, people thought life could just appear from non living matter • Ex – maggots just appear on meat
Redi’s Experiment • 1668 – proposed hypothesis that the maggots came from flies • Tested hypothesis by placing meat in jars and covering some of the jars • Everything was controlled (kept the same) except the variable (covering jars)
Uncovered jars Covered jars Several days pass Maggots appear No maggots appear Redi’s Experiment
Types of Variables • Independent: the variable being manipulated • Redi controlled the covering of the jars • Dependent: the variable that changes in response to the independent variable • The presence of maggots in Redi’s experiment
Flask is open. Gravy is teeming with microorganisms. Gravy is boiled. Flask is sealed. Gravy is free of microorganisms. Gravy is boiled. Spallanzani’s Experiment • Tested Redi’s results • Boiled to kill microorganisms • What are the independent and dependent variables??
Pasteur's Experiment • Provided final proof that spontaneous generation did not occur
Figure 1-11 Pasteur’s Experiment Section 1-2 Pasteur's Experiment Broth is boiled. Broth is free of microorganisms for a year. Curved neck is removed. Broth is teeming with microorganisms. Go to Section:
Pasteur's Experiment • What was Pasteur’s hypothesis? • Microorganisms would not just appear • Independent variable? • Curved neck of flask • Dependent variable? • Presence of microorganisms
Scientific facts are known to absolutely true after hundreds of repetitive trials of an experiment. • Fact: The world is round.
Myths: legends that express basic beliefs(made up stories that may be believed) • There are sewer fairies in the sewers of Las Vegas.
1. Define problem: Why do leaves change color? 2. Research: (Collect 5 sentences about the subject being studied. These must be in complete sentences, in your own words, and from an outside source). EXAMPLE OF A LAB WRITE-UP
Hypothesis: (Form an educated guess)
Hypothesis (Form an educated guess) • Logical, testable, tentative explanation for a set of observations or a possible answer to a scientific question • Arise from priorknowledge, logical inferences, or imaginative guesses
Testing hypotheses • Can be done through further observation • Usually done through controlled experiments • A hypothesis proven to be wrong still adds to the body of scientific knowledge
4. Experiment: (Also known as the procedure) • a. Place four different trees into four separate environments. • 1. Cold with daily decreasing light. • 2. Room temperature with uniform light from day to day. • 3. Cold with uniform light. • 4. Room temperature with daily decreasing light.
Types of Variables • Independent: the variable being manipulated • Dependent: the variable that changes in response to the independent variable
Variables: • LIGHT • TEMPERATURE • (Those factors actually causing there to be change)
Experimental setup: The part that will actually change. In this case the tree that loses color in its leaves.
Control setup: The part that does not do any changing at all because it is present to use as a comparison of what is “normal”.
6. Conclusion: (Explain results). • Temperature alone does not determine how many leaves don’t stay green. Decreasing day light also affected the variables.
https://glacier.qc.maricopa.edu/biology/scientific_method/index.cfmhttps://glacier.qc.maricopa.edu/biology/scientific_method/index.cfm • This will take you through the steps of the scientific method, set by step.
List of Equipment: A. Hand lens or magnifying glass