UNIT 1
The Nature of Science
UNIT OBJECTIVES
What Constitutes A Living Thing
Branches of Biology
Scientific Method Review
Units and Measurement Review
Unit Conversions Review
UNIT VOCABULARY
WHAT IS BIOLOGY
Bio = Life
Ology = Study
Biology = The Study of Life
WHAT DOES IT MEAN TO BE ALIVE?
9 characteristics determine whether or not something is alive.









1. Movement
2. Respiration
3. Sensitivity to Stimuli
4. Growth
5. Reproduction
6. Excretion
7. Nutrition
8. Cells
9. Evolution
MRS. GRENCE ACRONYM
Use the MRS. GRENCE Acronym to help you remember the nine
characteristics of life.
M
1. Movement
 Living Things Move.
MR
2. Respiration
Living Things Breath.
MRS.
Sensitivity to Stimuli
 Living Things Respond to Their Environment.
MRS. G
Growth
 Living things Grow
MRS. GRE
Reproduction
 Living Things Give Birth to New Life.
MRS. GRE
Excretion
 Living Things Create and Get Rid Of Waste.
MRS. GREN
Nutrition
 Living Things Need to Find Nutrients For Energy.
MRS. GRENC
Cells
 Living Things are Made of Cells
MRS. GRENCE
Evolution
 Living Things Evolve
HOMEWORK
Study these characteristics at home and be prepared for a quiz next
class period.
HOW DO YOU KNOW IF SOMETHING IS ALIVE?
Movement
Respiration
Sensitivity to stimuli
Growth
Reproduction
Excretion
Nutrition
Cells and
Evolution
MRS. GRENCE
M
HOW DO YOU KNOW IF SOMETHING IS ALIVE?
R
S
G
R
E
N
C
E
MRS. GRENCE
BRANCHES OF BIOLOGY
Synthetic Biology
Research
Doctor
Proteomics
Geneticist
Surgeon
Biotechnologist
Cardiologist
Professor
Paramedic
Zoo Curator
Surgeon
Nurse
Medicine
Biology
Sports Medicine Veterinarian
Physical Therapist
Forest Ranger
Anesthesiologist
Biological Quality
Assurance
Education
High School Teacher
Field Assistant
Conservation
Environmentalist
MAJOR BRANCHES OF BIOLOGY
Botany – The Study of Plants
Zoology – The Study of Animals (many subcategories)
Cytology – The Study of Cells
Ecology – The Study of Relationships and Energy Transfer Among
Living Things
Veterinary Science – The Study of Medicine for Animals
Anatomy – The Study of the Structure of Animals and Their Parts
MAJOR BRANCHES OF BIOLOGY
Evolutionary biology – The Study of Evolution
Paleontology – The Study of Extinct Organisms
Genetics – The Study of Genes
Agriculture – The Study of Farming
Medicine – The Application of Science to the Human Body for
Better Health
Epidemiology – The Study of How Disease Spreads
WHAT INTERESTS YOU ABOUT BIOLOGY?
If you absolutely had to become a Biologist, what branch would you
most be interested in studying. Explain your choice to me in a writing
prompt.
Writing prompt:
8 lines
SCIENTIFIC METHOD REVIEW
(a) Observation/Statement of problem
(b) Research
(c) State Hypothesis
(d) Experimental Setup – dependent, independent and control variables
(e.1) Observation and collection of data
(e.2) Organization of Data (e.g. – tables and graphs)
(f) Analysis of Data
(g) Conclusion
OBSERVATION/INFERENCE
Observation:
The act of describing the world
around us with our senses
OBSERVATION/INFERENCE
Inference:
A logical interpretation based on
our observations and previous
knowledge.
OBSERVATION OR INFERENCE ACTIVITY
TYPES OF OBSERVATIONS
Qualitative Observation: Describes the
quality (characteristic) of what you
see.
Exp: The lady bug is red.
Quantitative Observation: Describes the
quantity(number) of what you see.
Exp: The lady bug has 7 spots.
HYPOTHESIS
Hypothesis: A measureable
prediction based on
observation and research.
Must be testable
EXPERIMENTAL SET UP
Independent Variable:
The variable that is deliberately
changed by the experimenter
Dependent Variable:
The variable that the experimenter
measures.
Controlled Variables:
Variables that the experimenter
makes sure stays the same.
EXPERIMENTAL SET UP
Control Group:
The control group is exposed to the
same conditions as the experimental
group, except for one variable.
Experimental Group:
The experimental group is exposed to
the independent variable
EXPERIMENTAL SET UP PRACTICE
1. A study was created to test the effects of jazz on
people’s sleep patterns. The hypothesis of the experiment
was that if people listened to jazz music as they fall
asleep, they will sleep for longer periods of time. For the
experiment, 2 groups of people were created. One group
was placed in a quiet room where they went to sleep and
they were timed on how long they slept. The other group
was placed in a room where jazz music played softly as
they began to sleep and played throughout the night. As
each group awoke, their sleep times were monitored.
Independent Variable:
Dependent Variable:
EXPERIMENTAL SET UP PRACTICE
2. A study was created to test the effects of fear in
children. The hypothesis of the experimenters was that if
babies were exposed to fuzzy bunnies and at the same
time a loud cymbal was struck close behind them, then that
child would be afraid of all fuzzy things. Another group of
children would be exposed to bunnies without any loud
noises. The study was carried out as planned and as a
result, hundreds of young children developed fear of all
cute furry bunny rabbits.
Dependent Variable: ______________________
Control Group: __________________________
Independent Variable: ____________________
Experimental Group: _____________________
EXPERIMENTAL SET UP QUIZ
Suzie Q wants to know the effect of different colors of light on the
growth of plants. She believes that plants can survive best in white
light. She buys 5 ferns of the same species, which are all
approximately the same age and height. She places one in white
light, one in blue light, one in green light, one in red light and one in
the closet. All of the ferns are planted in Miracle-Grow and given 20
mL of water once a day for 2 weeks. After the two weeks, Suzie
observes the plants and makes measurements.
Hypothesis: If plant growth is affected by color of light, then white
light will produce the most plant growth.
1. Independent Variable:
3. Control Group:
2. Dependent Variable:
4.Experimental Group:
5.What could be the controlled variables?
6. What types of measurements can Suzie make on the plants to
determine how they did in different types of light?
AN APPLE A DAY…
An apple a day
keeps the doctor
away!
Is it true?
Get into groups and design an
experiment that would prove whether or
not an Apple a day really does keep the
doctor away.
Make sure you have a:




Control Group
Experimental Group
Independent/Manipulated Variable
Dependent/responding Variable
AHHH!!!!!
RAWR!!!!
PEER REVIEW
Present your experiment to
your peers.
But be skeptical. Could their
experiment really prove that
an apple a day keeps the
doctor away?
OBSERVATION AND COLLECTION OF DATA
Careful observation and measurement of
your dependent variable.
ORGANIZATION OF DATA
Organizing Data allows us to look for trends and helps us get a better
understanding of what happened.
ANALYSIS OF DATA
What does your data say?
CONCLUSION
What was learned.
Did you prove or disprove your hypothesis?
Ways to improve the experiment.
ONE OF THESE THINGS IS NOT LIKE
THE OTHER…
This guide will explain briefly the concept of units, and the use of a simple
technique with a fancy name—"dimensional analysis”.
WHATEVER YOU MEASURE, YOU
HAVE TO USE UNITS
• A measurement is a way to describe
the world using numbers. We use
measurements to answer questions like,
how much? How long? How far?
• Suppose the label on a ball of string
indicates that the length of the string is
150.
• Is the length 150 feet, 150 m, or 150 cm?
• For a measurement to make sense, it
must include a number and a unit.
UNITS AND STANDARDS
Number
150 feet
Unit
*Rule: No naked numbers. They must have units
• Now suppose you and a friend want to
make some measurements to find out
whether a desk will fit through a doorway.
• You have no ruler, so you decide to use
your hands as measuring tools.
UNITS AND STANDARDS
• Even though you
both used hands
to measure, you
didn’t check to
see whether your
hands were the
same width as
your friend’s.
UNITS AND STANDARDS
• In other words, you
didn’t use a
measurement standard,
so you can’t compare
the measurements.
• Hands are a
convenient measuring
tool, but using them
can lead to
misunderstanding.
UNITS AND STANDARDS
• So in order to avoid confusion we use
measurement standards.
• A standard is an exact quantity that
people agree to use to compare
measurements.
UNITS AND STANDARDS
• In the United States, we commonly use
units such as inches, feet, yards, miles,
gallons, and pounds. This is known as
the English system of measurement.
• Most other nations and the scientific
community use the metric system
- a system of measurement based on multiples of ten.
INTERNATIONAL SYSTEM OF UNITS
• In 1960, an improvement was made to
the metric system. This improvement is
known as the International System of
Units.
• This system is abbreviated SI from the
French Le Systeme Internationale
d’Unites.
INTERNATIONAL SYSTEM OF UNITS
• The standard kilogram is kept in Sèvres,
France.
• All kilograms used throughout the world
must be exactly the same as the kilogram
kept in France because it is the standard.
INTERNATIONAL SYSTEM OF UNITS
• Each type of SI
measurement
has a base unit.
• The meter is the
base unit of
length.
INTERNATIONAL SYSTEM OF UNITS
• Every type of
quantity measured
in SI has a symbol
for that unit.
• All other SI units are
obtained from these
seven units.
REVIEW
• When we measure something, we
always specify what units we are
measuring in.
• All kinds of units are possible, but in
science we use the SI system.
MEASUREMENT
Can you:
 (a) measure with a ruler in
centimeters?
 (b) measure liquid volume using a
graduated cylinder in milliliters?
 (c) mass in grams?
 (d) density in g/cm3?
HOW TO MEASURE PRECISION
Team1
Team2
Team3
Team4
Team5
Team6
Team7
2.65g
2.75g
2.80g
2.77g
2.60g
2.65g
2.68g
1. Find the average
1. Add up all the results and divide by the number of teams
1. 2.65+2.75+2.80+2.77+2.6+2.65+2.68/7
1. 2.72g
2. Find the margin of error.
1. Subtract the mean from your highest measurement and lowest
measurement
1. 2.80 -2.72 = 0.08
2. 2.72 – 2.60 = 0.12
3. Add your margin of errors together:
1. 0.08 + 0.12 = 0.20
4. Margin of error is 0.20g
HOW TO MEASURE ACCURACY:
PERCENT ERROR
Actual Value
Measured Value
5.55
6
Actual Value - Measured Value
%Error =
Actual
Value
X 100
MEASUREMENT LAB
Students will measure certain objects and collect accurate data.
MEASUREMENT
LAB
DATA
SHEET
Copy this table onto a piece of paper. You will be turning this paper in, so make it
neat and easy to read. Go around the classroom and get the measurements of the
items in the list. Record your measurement in the measurement column. When you are
done type your measurements into the Excel Spreadsheet on Ms. Roderick’s computer.
Object
Length of the
Classroom (m)
Width of the
classroom (m)
Height of the
classroom (m)
Cup 1 (mL)
Cup 2 (mL)
Paper clamp (g)
White Out (g)
Dice (g/cm3)
Your
Measurement
Actual
Measurement
Accuracy
Precision
ACCURACY AND PRECISION
Precision: Precision is how close the
measured values are to each other.
ACCURACY AND PRECISION
Accuracy: Accuracy is how close a
measured value is to the actual (true)
value.
ACCURACY AND PRECISION
Good Measurements are both
accurate and precise.
ACCURACY AND PRECISION VIDEO
MEASUREMENT
LAB
DATA
SHEET
Copy this table onto a piece of paper. You will be turning this paper in, so make it
neat and easy to read. Go around the classroom and get the measurements of the
items in the list. Record your measurement in the measurement column. When you are
done type your measurements into the Excel Spreadsheet on Ms. Roderick’s computer.
Object
Your
Measurement
Actual
Measurement
Length of the
Classroom (m)
1580.6 cm
Width of the
classroom (m)
642.6 cm
Height of the
classroom (m)
253.5
Cup 1 (mL)
91 ml
Cup 2 (mL)
27 ml
Paper clamp (g)
6.1g
White Out (g)
33.7g
Dice (g/cm3)
5 g/cm3
Accuracy
Precision
MEASUREMENT LAB
1. Record the actual measurements and
calculate your accuracy. Write in your
percent error under the accuracy column.
2. Using the measurements from your
classmates record the precision of your
measurements. Write your margin of
error in the precision column.
SOMETIMES YOU HAVE TO CONVERT BETWEEN
DIFFERENT UNITS
• How many seconds are in a day?
• How many inches are in a centimeter?
• If you are going 50 miles per hour,
how many meters per second are you
traveling?
• To answer these questions you need
to change (convert) from one unit to
another.
HOW DO YOU CHANGE UNITS?
• Whenever you have to convert a physical
measurement from one dimensional unit to
another, dimensional analysis is the
method used.
(It is also known as the unit-factor method or the factor-label method)
• So what is dimensional analysis?
The converting from one unit system to another.
If this is all that it is, why make such a fuss about it? Very
simple. Wrong units lead to wrong answers. Scientists have
thus evolved an entire system of unit conversion.
DIMENSIONAL ANALYSIS
• How does dimensional analysis work?
• It will involve some easy math (Multiplication & Division)
• In order to perform any conversion, you need a
conversion factor.
• Conversion factors are made from any two terms
that describe the same or equivalent “amounts”
of what we are interested in.
For example, we know that:
1 inch = 2.54 centimeters
1 dozen = 12
CONVERSION FACTORS
• So, conversion factors are nothing more than
equalities or ratios that equal to each other. In
“math-talk” they are equal to one.
• In mathematics, the expression to the left of the
equal sign is equal to the expression to the right.
They are equal expressions.
• For Example
12 inches = 1 foot
Written as an “equality” or “ratio” it looks like
=1
or
=1
CONVERSION FACTORS
or
Hey!
These
look like
fractions!
• Conversion Factors look a lot like fractions, but
they are not!
• The critical thing to note is that the units
behave like numbers do when you multiply
fractions. That is, the inches (or foot) on top and
the inches (or foot) on the bottom can cancel
out. Just like in algebra, Yippee!!
EXAMPLE PROBLEM #1
• How many feet are in 60 inches?
Solve using dimensional analysis.
• All dimensional analysis problems are set
up the same way. They follow this same
pattern:
What units you have x What units you want
What units you have
The number & units
you start with
The conversion factor
(The equality that looks like a fraction)
= What units you want
The units you
want to end with
EXAMPLE PROBLEM #1 (CONT)
• You need a conversion factor. Something
that will change inches into feet.
• Remember
12 inches = 1 foot
Written as an “equality” or “ratio” it looks like
60 inches x
=
5 feet
(Mathematically all you do is: 60 x 1  12 = 5)
What units you have x What units you want
What units you have
= What units you want
EXAMPLE PROBLEM #1 (CONT)
• The previous problem can also be written
to look like this:
• 60 inches
1 foot
= 5 feet
12 inches
• This format is more visually integrated,
more bridge like, and is more appropriate
for working with factors. In this format, the
horizontal bar means “divide,” and the
vertical bars mean “multiply”.
DIMENSIONAL ANALYSIS
• The hardest part about dimensional
analysis is knowing which conversion
factors to use.
• Some are obvious, like 12 inches = 1 foot,
while others are not. Like how many feet
are in a mile.
EXAMPLE PROBLEM #2
• You need to put gas in the car. Let's
assume that gasoline costs $3.35 per
gallon and you've got a twenty dollar bill.
How many gallons of gas can you get with
that twenty? Try it!
• $ 20.00
1 gallon
= 5.97 gallons
$ 3.35
(Mathematically all you do is: 20 x 1  3.35 = 5.97)
EXAMPLE PROBLEM #3
• What if you had wanted to know not how many
gallons you could get, but how many miles you
could drive assuming your car gets 24 miles a
gallon? Let's try building from the previous
problem. You know you have 5.97 gallons in the
tank. Try it!
• 5.97 gallons 24 miles
= 143.28 miles
1 gallon
(Mathematically all you do is: 5.97 x 24  1 = 143.28)
EXAMPLE PROBLEM #3
• There's another way to do the previous
two problems. Instead of chopping it up
into separate pieces, build it as one
problem. Not all problems lend
themselves to working them this way but
many of them do. It's a nice, elegant way
to minimize the number of calculations
you have to do. Let's reintroduce the
problem.
EXAMPLE PROBLEM #3 (CONT)
• You have a twenty dollar bill and you need
to get gas for your car. If gas is $3.35 a
gallon and your car gets 24 miles per
gallon, how many miles will you be able to
drive your car on twenty dollars? Try it!
• $ 20.00
1 gallon
24 miles
$ 3.35
1 gallon
= 143.28 miles
(Mathematically all you do is: 20 x 1  3.35 x 24  1 = 143.28 )
EXAMPLE PROBLEM #4
• Try this expanded version of the previous
problem.
• You have a twenty dollar bill and you need
to get gas for your car. Gas currently costs
$3.35 a gallon and your car averages 24
miles a gallon. If you drive, on average,
7.1 miles a day, how many weeks will you
be able to drive on a twenty dollar fill-up?
EXAMPLE PROBLEM #4 (CONT)
• $ 20.00 1 gallon 24 miles 1 day
$ 3.35
1 week
1 gallon 7.1 miles 7 days
= 2.88 weeks
(Mathematically : 20 x 1  3.35 x 24  1 x 1  7.1 x 1  7 = 2.88 )
DIMENSIONAL ANALYSIS
• So you can have a simple 1 step problem
or a more complex multiple step problem.
Either way, the set-up of the problem
never changes.
• You can even do problems where you
don’t even understand what the units are
or what they mean. Try the next problem.
EXAMPLE PROBLEM #5
• If Peter Piper picked 83 pecks of pickled
peppers, how many barrels is this?
• Peter Piper picked a peck of pickled peppers... Or so the rhyme
goes. (What in the world is a peck?)
• You need help for this one. As long as you
have information (conversion factors) you
can solve this ridiculous problem.
EXAMPLE PROBLEM #5 (CONT)
• Use this info: A peck is 8 dry quarts: a bushel is 4
pecks or 32 dry quarts; a barrel is 105 dry quarts.
•
WHAT?! Rewrite them as conversion factors if the info
is not given to you that way.
8 dry quarts
1 peck
or
1 peck .
8 dry quarts
32 dry quarts
1 bushel
105 dry quarts
1 barrel
4 pecks
1 bushel
or
or
or
1 bushel .
32 dry quarts
1 barrel .
105 dry quarts
1 bushel
4 pecks
EXAMPLE PROBLEM #5
• Pick the conversion factors that will help
get to the answer. 83 pecks
1 barrel.
Hint: Look for units that will cancel each other.
• 83 pecks 8 dry quarts
1 peck
1 barrel
105 dry quarts
= 6.3 barrels
(Mathematically : 83 x 8  1 x 1  105 = 6.3 )
REVIEW
• Dimensional Analysis (DA) is a method
used to convert from one unit system to
another. In other words a math problem.
• Dimensional Analysis uses Conversion
factors . Two terms that describe the same or equivalent
“amounts” of what we are interested in.
• All DA problems are set the same way.
Which makes it nice because you can do
problems where you don’t even understand
what the units are or what they mean.
TEST REVIEW
The Unit 01- The Nature of Science test will include the following
information:
 Characteristics of Life
 Be able to list the 9 characteristics of life and explain what they mean. (MRS. GRENCE)
 Scientific Method
 Make sure you know the steps of the scientific method.
 Experimental Set up
 Be able to determine the independent, dependent and controlled variables and control and experimental
groups of an experiment.
 Observation and Inference
 Be able to make observations and inferences and determine the difference between each.
 Measurement
 Know what units are used for specific measurements
 Accuracy and Precision
 Know the difference between accuracy and precision
 Be able to calculate percent error.
 Dimensional Analysis
 Be able to convert units using dimensional analysis.
 Branches of Biology
 Be able to write about a branch of biology that was interesting to you.