How to take:
Divide the paper into 3 sections
A vertical line 5
cm from the left.
A horizontal line
5 lines up from
the bottom.
Heading
Write the
title and
date of the
notes.
Title
Date
Take notes during lecture.
The large box is for
writing notes.
Skip a line between
slides.
Don’t use complete
sentences,
abbreviate and use
symbols when you
can.
Title
Date
Study Questions
Review your notes
after class and write
down study
questions, key points
or vocabulary.
Summarize
Write a summary
at the end of the
notes.
Study your notes
Review your
notes.
Quiz your self
with the study
questions.
Review your
summaries.
UNIT 1
Introduction:
Scientific Method
& Biology Today
Scientific Method
The Process of Science
• The word science is derived from a Latin verb
meaning “to know.”
– Science is a way of knowing.
– Science developed from people’s curiosity about
themselves and the world around them.
• Science seeks natural causes for natural
phenomena.
– This limits the scope of science to the study of
structures and processes that we can observe and
measure.
Discovery Science
• Verifiable observations and measurements are the
data of discovery science.
– In biology, discovery science enables us to
describe life at its many levels.
Hypothesis-Driven Science
• As a formal process of inquiry, the scientific method
consists of a series of steps.
– The key element of the
scientific method is
hypothesis-driven
science.
Hypothesis-Driven Science
• A hypothesis is a tentative answer to some
question.
– It is an explanation on trial.
• Once a hypothesis is formed, an investigation can
test the hypothesis
• the hypothesis is tested by performing an
experiment to see whether results are as predicted.
The Scientific Method
A series of steps that are used to solve
a problem or better understand an
event.
Observation
We can do observations BEFORE conducting
an experiment.
This allows us to start thinking about what we
are seeing.
1. Asking a Question
Based on observations; one or more research
questions are generated
Ex. What is the
effect of sunlight on
plant growth?
More Observation/Research
Observe the world using your senses
(sight, sound, taste, touch, smell) and
research your problem using the
internet or books or journals.
Inference: involves
a judgment
or assumption
2. Forming A Hypothesis
• hypo (less than) thesis (theory)
• Explanation for what you have seen and
recorded in your prior obsevervations.
Predict a solution to the problem based on
your research.
• An educated guess
• a question or statement that can be tested.
Ex. If sunlight has an effect on plant growth, then plants
will grow larger in the sun because it is needed for
photosynthesis.
Forming a Hypothesis Continued…
1. Statement is testable if evidence can be collected
that either does or doesn’t support it
2. It can never be proven beyond doubt
3. Often must be refined and revised or discarded
Predicting
• To test hypothesis it is necessary to make
predictions that logically follows from the
hypothesis
• A statement made in advance that states the
results that will be obtained from testing the
hypothesis
• Often in the form of an “if-then” statement
3. Experiment
A procedure to test a hypothesis, under
controlled conditions – conducting a
controlled experiment.
It is clear and detailed so another scientist
can replicate your experiment.
List all materials.
Controls & Constants
 Constant
Control group
(controlled
The group or sample that variable)
The factors in the
experiment that need to
stay the same between
Ex. The plant in the dark
the experimental group
(compare to plants in
and the control.
different amounts of
Ex. amount of soil,
light).
nutrients, water is the
SAME for all plants
is used as a standard
for comparison.
3 Kinds of Variables
1. Controlled Variable – a variable that is not
changed
• Also called constants
• Allow for a “fair test”
Controls ensure that all variables in the experiment
are the same except for the variable being tested.
24
3 Kinds of Variables
2. Independent Variable – something that is
changed by the scientist
• What is tested (the treatment)
• What is manipulated
25
3 Kinds of Variables
3. Dependent Variable – something that might be
affected by the change in the independent variable
• What is observed
• What is measured
• The data collected during the investigation (the
result of the treatment)
26
For Example:
27
Students of different ages
were given the same jigsaw
puzzle to put together. They
were timed to see how long it
took to finish the puzzle.
28
Identify the variables
in this investigation.
29
What was the independent variable?
Ages of the students
• Different ages were tested by the scientist
30
What was the dependent variable?
The time it to put the puzzle together
• The time was observed and measured by
the scientist
31
What was a controlled variable?
Same puzzle
• All of the participants were tested with the
same puzzle.
• It would not have been a fair test if some
had an easy 30 piece puzzle and some
had a harder 500 piece puzzle.
32
Another example:
33
An investigation was done
with an electromagnetic
system made from a battery
and wire wrapped around a
nail. Different sizes of nails
were used. The number of
paper clips the electromagnet
could pick up was measured.
34
What are the variables
in this investigation?
35
Independent variable:
Sizes of nails
• These were changed by the scientist
36
Dependent variable:
Number of paper clips picked up
• The number of paper clips observed and
counted (measured)
37
Controlled variables:
Battery, wire, type of nail
• None of these items were changed
38
One more:
39
The higher the temperature of
water, the faster an egg
will boil.
40
Independent variable – temperature of water
Dependent variable – time to cook an egg
Controlled variable – type of egg
41
Last one:
42
The temperature of water was
measured at different depths
of a pond.
43
Independent variable – depth of the water
Dependent variable – temperature
Controlled variable – thermometer
44
Designing Investigations
45
The greater the amount of soap in a
soap and water mixture, the bigger a
soap bubble can be blown.
Design an investigation to test this hypothesis.
• Identify the variables
• What exactly will be changed? How will it be
changed?
• What exactly will be measured? How will it be
measured?
46
The farther a ball drops, the higher it
will bounce.
Design an investigation to test this hypothesis.
• Identify the variables
• What exactly will be changed? How will it be
changed?
• What exactly will be measured? How will it be
measured?
47
4. Collecting Data
Data: The information collected from an
experiment.
Data is data, it isn't right or wrong - presented in
tables, charts, notes or diagrams.
Two Types
• Quantitative
• Qualitative
48
Types of Data
• Quantitative Data
– quantity - measured in numbers
• Qualitative Data
– quality - measured in words
(descriptions)
AND
•Observation - recognizing and noting some FACT to
gather information about the world
•You make observations using your five senses
•Observations must be specific and accurate, not
relative, so that it means the same to everyone.
•Example:
•Incorrect - the burning bag smelled nasty
•Correct - the burning bag smelled similar to
rotten eggs
•Inference - a possible explanation or guess
about an observation
•Example: you leave the movie theater and
see the ground is wet so you infer that it
rained.
The picture shows the label on a
carton of orange juice. Which of
these is supported by the
information on the label?
a. Orange juice turns all vitamins into
vitamin C.
b. Orange juice provides vitamin C to
the body.
c. Orange juice removes vitamin C to
the body.
d. Orange juice cause the body to need
vitamin C
The table in dictates the amount of time that four different brands of
batteries worked in a flashlight. Which of the following
statements is supported by this information?
A. Brand “A” caused the light to shine farther than the other brands.
B. Brand “M” lasts longer than the other brands.
C. Brand “ N” gave off a stronger light than the other brands
D. Brand “O” is more expensive than the others.
An advertisement for a breakfast food
states that the product is the “healthiest
choice”. Which of these could show
that this is a valid claim?
A. The bar code
B. The nutrition information
C. The number of grams
D. The pictures on the box
The picture shows a bottle of “Fun Sun
Cream”. Which of these statements
indicates how well this product helps
prevent skin damage?
A. Great for all outdoor activities
B. Contains the finest ingredients
C. Sun protection factor (SPF) 30
D. Money-back guarantee
Q
R
S
Which of these foods would be the best choice for
someone on a low-fat, low sodium diet?
A. Q
B. R
C. S
D. T
T
5. Analyzing Data
Make interpretations of
data by graphing data,
correlating data with
facts, using
mathematical analysis
etc.
6. Conclusions & Reporting of Data
Report data - put your numbers into words.
Answer: What was found out and how do
you know it to be true? How did it relate to
your hypothesis? Did it support or fail to
support?
60
Communication
Share the results of their studies with other
scientists
Publish findings in journals or at scientific
meetings
Sharing of information is essential to scientific
process
Subject to examination and verification by other
scientists
Allows scientists to build on the work of others
61
Analyze process and repeat
All valid data is reproducible
62
Forming a Theory
A theory may be formed after many related
hypotheses have been tested and supported with
experimental evidence
A broad and comprehensive statement of what is
thought to be true
Supported by considerable evidence
Ties together related hypotheses
Theory
Explanation supported by a large amount of
evidence obtained from many different
investigations over a long period of time.
Common Misconception: Theory defined as a
guess is not the scientific definition.
Example: Theory of Evolution
64
Law
Generally less complex than theories
A theory explains a law.
Examples: Law of Gravity, Law of Conservation of
Energy, Law of Conservation of Matter
65
Law vs. Theory
Law: A rule of nature that sums up related
observations and experimental results to describe
a pattern in nature (states WHAT happens).
Law of Gravity, Laws of Motion
Theory: A logical explanation of WHY or HOW
things work the way they do, based on many
observations supported by experimental results.
Atomic Theory, Big Bang Theory
 Theories can serve as explanations of laws!
 Both laws and theories can be changed or discarded if
new observations show them to be incorrect!
Measurements
We will be using SI (International System of
Measurement ) units or metric system when
possible --- get use to it --- the WHOLE world
uses it except us (USA)
Examples: length in meters, volume in liters,
temperature in Celsius, mass in grams and
time in seconds.
Did You Know?
Biology and Society:
Living in a Golden Age of Biology
• We are living in a golden age
of biology.
– Modern biology is as
important as it is inspiring,
with exciting breakthroughs
changing our very culture.
The Scope of Life
• Biology is the scientific study of life.
Biology
Bio (life) ology (study of)
– Life is structured on a
size scale ranging from
the molecular to the
global.
– Biology’s scope stretches
across the enormous
diversity of life on Earth.
The Unity of Life
• The phenomenon
we call life defies
a simple, onesentence definition
• There are several
characteristics of
living things.
Seahorse
Camouflage
Characteristics of Living Things
75
1. Cells
All living things are
composed of cells
76
Cells and Their DNA
• The cell is the lowest level of structure that
can perform all activities required for life.
– All organisms are composed of cells.
Generalized Cell
2. Organization / Order
Living things are organized
All structures have a function
• There are many MANY ways
to look at organization
– Molecular organization
– Cellular organization
– Organ/tissue organization
– Gender, size, systems, etc
78
Example:
In multicellular
organisms cells
and groups of cells
(tissues) are
organized by their
function
• Cells  tissues
• Tissues  organs
• Organs  systems
• Systems organism
Organization
Cellular Organization
Systemic Organization
3. Energy
All living things use energy in a
process called metabolism.
• The sum of all chemical processes that
occur in an organism.
81
Energy
The ability to do work. Work is anything that causes
motion. Work is required to be a living thing.
Every living thing uses energy from some of the
materials in food as fuel for the functions needed to
keep it alive.
82
Autotrophs
• Organisms that make their
own food are called
autotrophs
– Phototrophs – use solar
energy (photosynthesis) to
get energy
• Convert H2O and CO2
into sugar and O2
– Chemotrophs – use
different chemical
processes to get energy
83
Energy continued
Almost all energy comes from the sun (directly or
indirectly)
• Photosynthesis is the process by which some
organisms capture the energy from the sun (solar)
and transform it into energy (chemical) that can be
used by living things
84
Heterotrophs
Organisms that must take in food to meet their
energy needs are called heterotrophs
Consume autotrophs (herbivores), other
heterotrophs (carnivores) or both (omnivores)
for their energy needs
Complex chemicals are broken down and
reassembled into chemicals and structures
needed by organisms
85
4. Adaptation
86
Adaptation
Any structure, behavior, or internal process that
enables an organism to respond to stimuli and
better survive in an environment.
Ability to adapt to their environment through the
process of evolution
Favorable characteristics are selected for and
passed on to offspring
87
Evolution
• The gradual accumulation of adaptations over
time.
• Change over time.
5. Reproduction
All species have the ability to reproduce
• Not essential to survival of individual but is
essential for continuation of a species
89
Species
Donkey
Horse
A group of organisms
that can interbreed and
produce fertile offspring
Mule
Reproduction
All living things have the ability to reproduce and
pass on their genetic material (DNA) to their
offspring.
Living organisms can reproduce asexually or
sexually
Sexual reproduction involves an egg and sperm.
Asexual reproduction takes the form of cloning,
budding, root propagation, or self fertilization.
5. Growth & Development
•Growth is increasing in size over time.
•Development is changing toward final adult
form.
92
6. Respond to the Environment
Respond to stimuli in the external environment.
93
Environment
An organisms surroundings, which includes the air,
water, weather, temperature, and any other
organisms in the area.
Stimulus
A condition in the environment that causes an
organism to adjust.
Response
The reaction to a stimulus.
96
Homeostasis – An example of how your body responses
homeo (same) stasis (steady state)
Stability and homeostasis
Regulation of internal conditions in order to adjust to
external environment. Maintain very stable internal
conditions
Example: temperature 37°
hot-perspirecools cold-shiverwarms Other
examples include: water content, chemical content,
etc.
98