What is Science
• SCIENCE: Is using evidence to learn about the
natural world
• The Goal of Science
1.) Deals only with the natural world
2.) To collect and organize data
3.) Propose explanations that can be tested
What is Biology?
• Biology
• (bio = life and –ology = The study of)
• Biology = The study of life!
Scientific Method
• “One of the best ways to begin science is to
examine how scientist try to solve problems or
answer questions”
Observing & Asking Questions
• Science ALWAYS begins by observing and
asking questions
• Example: Do plants with more light grow
better than plants with less light?
• Other Possible Questions?
Hypothesizing
• Hypothesis- is a statement that both explains
your observations and data and must be
testable
• Create an “if-then” Prediction
• IF the plants receive more light THEN they will
grow larger.
Experimenting
• Most experiments are controlled experiments
• Parts to a controlled experiment
– Controlled group (standard or normal)
– Experimental group
– Independent variable (one factor you change)
– Control Variable (factors we keep the same)
– Dependent variable (depends on the independent
Variable)
Control Group
• Control Group: The normal or the group that
we compare our experimental group to.
(example: The normal plant that is by the
normal amount of light)
Control Variables
• Variable that do not change in an experiment
• Examples
– Soil
– Pots
– Plants
– Amount of Water
Independent Variable
• The Variable you change
• The amount of light the plants receive
• Placed on the X axis on a graph
Dependent Variable
• The Variable that is measured (Depends on
the independent Variable)
• The height of the plants
• Placed on the Y axis on a graph
Collecting Data
• Longest phase of a scientific investigation.
• Data includes any and all information that
scientist gather in trying to answer their
question.
• All data must be measureable (metric system
used in science)
What is DATA
• Two types of data
– 1.) Quantitative data = NUMBERS
– 2.) Qualitative data = DESCRIPTIVE WORDS
Drawing Conclusions
• Analyzing your data so that you can determine
if your hypothesis was correct or incorrect.
• Forming a theory. A theory is NOT a “wild
guess” it is NOT a hypothesis, but rather a
statement of what is thought to be true.
• A theory is supported by evidence.
What They Found
• Plants with more light grew better than plants
with less light
Plants in Closet
Plants near window
Plants outside
Try This
Bart believes that mice exposed to radiowaves will become extra
strong (maybe he's been reading too much Radioactive Man).
He decides to perform this experiment by placing 10 mice near a
radio for 5 hours. He compared these 10 mice to another 10
mice that had not been exposed. His test consisted of a heavy
block of wood that blocked the mouse food. he found that 8 out
of 10 of the radiowaved mice were able to push the block away.
7 out of 10 of the other mice were able to do the same.
Identify the11. Control Group
12. Independent Variable
13. Dependent Variable
14. What should Bart's conclusion be?