NATURE OF SCIENCE & LIFE
Professor Andrea Garrison
Biology 11
Nature Science
Process of asking questions
2
Nature Science
Process of asking questions
Questions that involve logical reasoning
3
Nature Science
Process of asking questions
Questions that involve logical reasoning
2 types logical reasoning
4
Nature Science
Process of asking questions
Questions that involve logical reasoning
2 types logical reasoning
Deductive reasoning
5
Nature Science
Process of asking questions
Questions that involve logical reasoning
2 types logical reasoning
Deductive reasoning
Inductive reasoning
6
Nature Science
Deductive reasoning
Applies general principal to specific cases
7
Nature Science
Deductive reasoning
Applies general principal to specific cases
Used to test validity of scientific idea
If principle does not work in specific situation, it isn’t a
valid principle
8
Nature Science
Deductive reasoning
Applies general principal to specific cases
Used to test validity of scientific idea
If principle does not work in specific situation, it isn’t a
valid principle
Much of our everyday life is run by deductive
reasoning (applying the principles we’ve learned
to new situations)
9
Nature Science
Inductive reasoning
Determines general principles from examination
of specific cases
10
Nature Science
Inductive reasoning
Determines general principles from examination
of specific cases
General principles explain how & why phenomena
occur
11
Nature Science
Inductive reasoning
Determines general principles from examination
of specific cases
General principles explain how & why phenomena
occur
General principles can applied later to other
situations (used deductively)
12
Nature of Science
Many possible explanations for how/why
How do we know which is correct?
13
Nature of Science
Many possible explanations for how/why
How do we know which is correct?
Use
Scientific Method
14
Scientific Method
Observation
Question
Hypothesis
Experiment
Prediction
Run experiment
Analysis
Accept/reject hypothesis
15
Scientific Method
Observation about phenomenon you find
interesting
16
Scientific Method
Observation about phenomenon you find
interesting
Question (eg, why does it happen that way?)
17
Scientific Method
observation about phenomenon you find
interesting
question (eg, why does it happen that way?)
Develop hypothesis (possible answer to
question)
18
Scientific Method
Hypothesis must be valid
19
Scientific Method
Hypothesis must be valid
Cause and effect
20
Scientific Method
Hypothesis must be valid
Cause and effect
Only one variable
21
Scientific Method
Hypothesis must be valid
Cause and effect
Only one variable
Be testable
22
Scientific Method
Hypothesis must be valid
Cause and effect
Only one variable
Be testable
Not anthropomorphic
Not imply human emotions to non-human entity
23
Scientific Method
Hypothesis must be valid
Cause and effect
Only one variable
Be testable
Not anthropomorphic
Not imply human emotions to non-human entity
Not teleological
Not imply purpose
24
Scientific Method
Design experiment to test hypothesis
25
Scientific Method
Design experiment to test hypothesis
Make prediction as to outcome of experiment
If I (explain expt), then (predict outcome)
26
Scientific Method
Design experiment to test hypothesis
Make prediction as to outcome of experiment
If I (explain expt), then (predict outcome)
Run experiment and record results
27
Scientific Method
Design experiment to test hypothesis
Make prediction as to outcome of experiment
If I (explain expt), then (predict outcome)
Run experiment and record results
Analyze results
28
Scientific Method
Design experiment to test hypothesis
Make prediction as to outcome of experiment
If I (explain expt), then (predict outcome)
Run experiment and record results
Analyze results
Provisionally accept hypothesis if prediction
correct –OR- reject hypothesis if prediction
incorrect
29
Scientific Method
30
Scientific Method
Provisionally accepted hypothesis not
immediately accepted as fact
31
Scientific Method
Provisionally accepted hypothesis not
immediately accepted as fact
Scientists open to new evidence which might
disprove hypothesis
32
Scientific Method
Provisionally accepted hypothesis not
immediately accepted as fact
Scientists open to new evidence which might
disprove hypothesis
Spontaneous generation
Mice recipe
33
Scientific Method
Provisionally accepted hypothesis not
immediately accepted as fact
Scientists open to new evidence which might
disprove hypothesis
Spontaneous generation
Mice recipe
Flies
34
Scientific Method
Provisionally accepted hypothesis not
immediately accepted as fact
Scientists open to new evidence which might
disprove hypothesis
Spontaneous generation
Mice recipe
Flies
Red wine & cardiovascular disease
35
Scientific Method
Theory
Hypothesis which has never been proven wrong
Great amount of evidence
36
Scientific Method
Theory
Hypothesis which has never been proven wrong
Great amount of evidence
Can be used to predict natural phenomena
37
Scientific Method
Theory
Hypothesis which has never been proven wrong
Great amount of evidence
Can be used to predict natural phenomena
Science (including Biology) based on theories
Hypotheses which are consistent with
observations and never proven wrong
38
What criteria qualify as scientific?
39
What criteria qualify as scientific?
Must be observable
Must be able to be tested
Must be falsifiable
40
What criteria qualify as scientific?
Must be observable
Must be able to be tested
Must be falsifiable
Ideas that are not observable or testable
Beliefs
Not necessarily wrong
Not science
41
Mechanism vs. Vitalism
Mechanism
Science
Holds to philosophy that universe governed by set
of natural laws that explain all events
42
Mechanism vs. Vitalism
Mechanism
Science
Holds to philosophy that universe governed by set
of natural laws that explain all events
Vitalism
Religion
Holds to philosophy that universe governed by
supernatural power(s) that guide behavior of
natural phenomena, gave rise to life, etc.
43
Mechanism vs. Vitalism
Mechanism and vitalism not mutually
exclusive
44
Mechanism vs. Vitalism
Mechanism and vitalism not mutually
exclusive
Basic science does not incorporate vitalistic
ideas (even though they may be RIGHT)
Not testable
45
NATURE OF LIFE
What is life?
46
NATURE OF LIFE
What is life?
General concept that is usually applied
Movement
Response to stimuli
Need food
Die
47
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
48
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
1. Composed of one or more cells
49
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
1. Composed of one or more cells
2. Metabolism (use energy to maintain life and grow)
50
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
1. Composed of one or more cells
2. Metabolism (use energy to maintain life and grow)
3. Capable of reproduction
Cells
Offspring
51
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
1. Composed of one or more cells
2. Metabolism (use energy to maintain life and grow)
3. Capable of reproduction
Cells
Offspring
4. Possess genetic material
52
Nature of Life
Criteria that will always work (not those listed
in text)
All five must be present
1. Composed of one or more cells
2. Metabolism (use energy to maintain life and grow)
3. Capable of reproduction
Cells
Offspring
4. Possess genetic material
5. Homeostasis (maintain constant internal environment
even when external environment is changing)
Salinity, pH, sometimes temperature
53
Nature of Life
Other traits often listed
54
Nature of Life
Other traits often listed
Response to changes in internal and external
environment
Pain, danger, temperature, etc.
55
Nature of Life
Other traits often listed
Response to changes in internal and external
environment
Pain, danger, temperature, etc.
Evolve over time
Natural selection insures best fit genetic variation
survive
56
Nature of Life
Some non-living entities can have major
impact on living organisms in a manner that
makes us want to call them “living”
57
Nature of Life
Some non-living entities can have major
impact on living organisms in a manner that
makes us want to call them “living”
Viruses
58
Nature of Life
Some non-living entities can have major
impact on living organisms in a manner that
makes us want to call them “living”
Viruses
Prions
59
Nature of Life
Some non-living entities can have major
impact on living organisms in a manner that
makes us want to call them “living”
Viruses
Prions
These entities are not alive
60
Nature of Life
Some non-living entities can have major
impact on living organisms in a manner that
makes us want to call them “living”
Viruses
Prions
These entities are not alive
Do not meet 5 criteria to be considered living
61