Chapter 2
The Science of Biology
Targets:
• Describe the nature of scientific inquiry
• Summarize the nature of discovery science
• Outline the generalized steps of the hypothesis-based
science
• State how the terms evidence, hypothesis, and theory are
used in science.
Think, Pair, Share
Answer the following questions by yourself:
1. What is science?
2. How do we do science?
3. What is not science?
Pair up with the person seated beside you
and share your answers.
What is the Nature of Scientific
Inquiry?

It’s a way of understanding the natural
world by asking questions and actively
seeking to answer them.
What is Discovery Science?
Describes nature.
 Emphasizes inquiry and observation.

Observation is the use of the senses to gather
information.
Observations may be descriptive (qualitative)
 Observations may be measurements (quantitative)

An inference is a logical conclusion based
on observations.
 Example: Jane Goodall’s work with
chimpanzee behavior.

What is Hypothesis-Based Science?

Explains nature by applying the scientific method to
problems.
Recognize the Question
After making observations, scientists ask questionsWhy? What if? How?
What effect does _________have on_________?
Experimental (Independent) Variable: the one variable that you
change
Dependent Variable: the one variable that you measure
(HINT: D = Data)
What effect do 0, 1, 2, or 3
cans of pop have on
performance on a memory
test?
Develop a Hypothesis
After collecting data, scientists ponder explanations…
• explains observations and can be tested.
• written as an “If…then…” statement.
If the amount of pop consumed increases,
then the performance on a memory test will
decrease.
Experimental/Independent Variable
Dependent Variable
Test the Hypothesis
Controlled Experiment…
•All variables stay the same EXCEPT the experimental
variable
•Control group vs. the experimental group
Control group: students who do not drink pop.
Experimental group: students who drink 1, 2, or 3 cans
of pop.
Analyze the Data

Scientists then study the data and look
for differences between the groups.
What trends do you notice
about reading, math, and
language scores between
1997 to 2000?
Which one changed the
most significantly? How do
you know?
Reach Conclusions & Share New
Knowledge

Accept or reject the hypothesis based on
results and discuss the experimental
process.

Share findings with scientific community
so that new questions can be generated.
How are the terms Evidence,
Hypothesis and Theory used in
science?

Evidence: collected body of data from
observations and experiments.
→It
needs to be repeatable.
Hypothesis: Must be able to meet the
standard of testability and be falsifiable.
Theory: a well-tested explanation that
makes sense in a great variety of scientific
observations.
http://notjustatheory.com/
Wrapping it Up: Answer the
targets.
1.
2.
3.
4.
Describe the nature of scientific inquiry.
Summarize the nature of discovery
science
Outline the generalized steps of the
hypothesis-based science
State how the terms evidence,
hypothesis, and theory are used in
science.