Chapter One
Section 1-1
THE SCIENCE OF BIOLOGY
Scientific Thought Involves:
 Questioning ideas-Scientists must be skeptical of
new ideas. Rely on evidence not opinions
 Discovery and change- Scientists must realize that
new discoveries may change old ideas. Examples?
Universal laws are…
 Definition of a universal law:
A truth that scientist have found to be true
everywhere in the universe.
-Law of gravity
-Law of conservation
of energy.
Science and Ethics
 What does it mean to be ethical?
-To have moral principles and values.
 What are some ways that you would expect a
scientist to be ethical?
-Providing true and accurate data.
-Not making false claims.
-Not using involuntary subjects.
-Obey laws.
Why study science?
 Critical thinking skills.
 Better take care of your health, better understanding
of health.
 Wiser consumer.
 Better informed citizen.
Chapter 1
Section 2
Scientific Method
Evidence Based on Observation
 Observation
-Using one or more senses to
perceive objects and events.
Data
-Information gathered from observation (evidence).
The scientific method
 A systematic approach to problems solving.
 Can be used by anyone, even for non-scientific
problems!
Step One
 1. Make an OBSERVATION.
 Is
the act of noting or perceiving objects or events.
 Observations lead to a question or problem.
 Example: Some flowers grow taller than others. I
wonder if the amount of fertilizer changes the height?
Step Two
 2. Form a HYPOTHESIS.
A
hypothesis is a possible explanation
to a problem that can be tested by experiments.
 Should
be written in an “if…then” format
 Testable-
Must be able to collect data on the
hypothesis (numbers, observations, make
inferences).
Hypothesis
 Example hypothesis:
If I apply 0 tsp, 1 tsp, 2
tsp and 3 tsp of fertilizer
on the plants, then the
beans with 2 tsp of
fertilizer will grow the
tallest.
Step Three
3. Conduct a controlled EXPERIMENT.
 A procedure that is carried out under controlled
conditions to test a hypothesis.
 Control- is the standard for comparison. Usually the
“normal” conditions.
 Example- The control for the bean experiment would
be the plant that received zero tsp. of fertilizer.
Step Three: EXPERIMENT
 Constants- the parts of an experiment that stays the
same for all trials.
 Example: In the plant experiment the amount of
light would have to remain constant for all of the
plants being tested.
Step Three: EXPERIMENT
 Independent
variable: The factor that scientists
change in the experiment.
 Example: Amount of fertilizer.
 Dependant
variable: The factors that change in
response to the independent variable. (What we
are trying to observe).
 Example: Height of the plants.
Step Four
 ANALYZE RESULTS:
 Look at data collected, use it to accept or
reject the hypothesis.
 Example: In the plant you would look at data
to see which plants grew the tallest.
Step Five
 5. Draw a CONCLUSION.
 After you have analyzed data decide whether
or not your hypothesis is accepted or
rejected.
 It’s OK if it is rejected!
 Example: The plant with 1 tsp. of fertilizer
grew the tallest, therefore our hypothesis is
rejected.
Step Six
 CONSIDER BIAS AND REPEAT
 Think about reasons why the experiment may have
been bias.
 Example: Was the plant experiment funded by an
organic foods farm?
 Repeat the experiment to see if you get the same
results.
 May lead to a new hypothesis.
What are the steps of the scientific method?
1.
2.
3.
4.
5.
6.
What is a Scientific Theory?
 Theory= When a hypothesis is well supported and
can be used to explain a broad range of data.
 For example: The “Cell Theory” states that all living
things are made up of cells.
Steps to Constructing a Theory
Chapter One
Section Three
Tools of Biology
How do scientist measure?
 Using SI=the International System of Units
otherwise known as the “metric system.”
 Everything is scaled in multiples of 10 to make it
easier to use.
 Most of the world uses this system for measuring.
Common SI Units
Factor
Volume
Length
Mass
1,000
1 kiloliter=
1,000 L
1 kilometer=
1,000 m
1 kilogram
=1,000 g
1
1 liter (L) 1 meter
(m)
Centi-
0.01
1 centiliter= 1 centimeter= 1 centigram
0.01 L
=0.01 g
0.01 m
Milli-
0.001
1 millimeter 1 millimeter= 1 milligram
=0.001 L
=0.001 g
0.001 m
Prefix
Kilo-
1 gram
(g)
Lab Techniques
 Microscopy-Using microscopes to magnify objects
too small for the unaided eye.
 Sterile techniques- A method to keep unwanted
bacteria off of equipment.
 Collecting data remotely- using tools such as GPS to
track animals.
Sterile Technique
Parts of the microscope
Proper Way to Carry a Microscope
A Few Other Tools to Know:
Graduated Cylinder
Erlenmeyer Flask
Lab Safety:
 Follow verbal and written instructions EXACTLY.
 Never touch broken glass.
 Keep purses, bags, extra books and other clutter off
of the lab tables.
 If there is any type of emergency remain calm and
tell your teacher immediately.
 Pay attention to what you are doing and do not
wander around the room.
Chapter One
Section Four
What is Biology
Biology is:
 Biology is the study of ALL life.
Biology Includes:
 Biochemistry-The study of chemistry in living things.
 Ecology-The study of the environment.
 Microbiology-The study of microscopic living things.
 Botany- The study of plants.
 Zoology-The study of animals.
 Anatomy-The study of body structure.
All Living Things have 7 Characteristics of Life
1.
2.
3.
4.
5.
6.
7.
Cells- All living things are made of at least one cell.
Homeostasis-Maintain internal conditions.
Metabolism- The sum of all chemical rxn in the
body.
Reproduction- All living things have the ability to
reproduce.
Responsiveness- Respond to the environment.
Heredity- All living things can pass on DNA to
offspring.
Growth- All living things grow and develop with
age.
1. Cells
 Every living thing is made up of at least one cell:
2. Homeostasis
 Homeostasis=When an organism maintains a
stable internal environment.
3. Metabolism
 Metabolism=Any chemical reaction that occurs in
a living body. (All living things do this).
4. Responsiveness
 All living things respond to their environment.
5. Reproduction
 Reproduction=The process by which organisms
make more of their own kind from one generation to
the next.
6. Heredity
 Heredity=When an organism passes on it’s traits to
offspring through DNA.
 All living things contain DNA in their cells.
7. Growth
 All living things grow. Some for a short period of
time and some for thousands of years like the
sequoia.