Nature of Science 1
What is the first step in most scientific investigations?
Ask a question or identify a problem.
A tentative, testable explanation for an observation or phenomenon that guides scientific research
Hypothesis
Why might scientists revise a scientific model?
New evidence or improved technology may reveal that the model needs to be updated.
Measurements or observations collected and recorded in an experiment or investigation are known as
data
How many independent and dependent variables should there be in order to have a valid science experiment?
One
What is an independent variable?
the part of an experiment being changed or manipulated
A factor that is kept the same throughout an investigation.
Control/Constant Variable
A student changes the amount of sunlight each plant receives and measures plant growth. What is the independent variable?
The amount of Sunlight
Four groups of rats are first weighted and then fed identical diets except for the amount of vitamin A. Each group gets a different amount of vitamin A. After 3 weeks on the diet, the rats' weights are measured again to see if they have lost weight. The dependent variable in this experiment is
The weight of the rats.
What do you call a controlled procedure with independent and dependent variables carried out to test a hypothesis.
Experiment
What is an observation?
Information gathered using your senses or scientific tools.
One person Repeating the experiment over and over
Repetition
What should a scientist do if the results do not support the hypothesis?
Rewrite their hypothesis and try the experiment again
An scientific study of the natural world that does not have independent or dependent variables is an
investigation
A simplified representation of a real system or concept used to explain, predict, or understand it (What is a globe?)
Model
What is the Dependent Variable?
The outcome of the independent variable (what is being measured)
When another scientist repeats someone else's experiment to verify whether the results are fair (copying)
Replication
A student tests how surface type affects the distance a toy car travels. What is the independent variable?
The type of surface.
Using one or more of your senses to gather information is called
observing
What is the main purpose of a scientific law?
To describe what happens under certain conditions in nature.
What is the Control group?
The group that stays the same and not given any changes in the experiment. Does not receive independent variable.
To summarize the results and state whether the hypothesis was correct
Conclusion
How should a hypothesis be written?
If (independent variable change), then (dependent variable outcome)
What is the main purpose of a scientific theory?
To explain how or why a natural phenomenon occurs.
Scientists observe that planets move in predictable elliptical paths around the Sun. Kepler’s description of this pattern is a theory or law?
A scientific law—Kepler’s laws of planetary motion.