Download Unit 1: Introduction to Biology and Scientific Methods

Unit 1: Introduction to Biology
and Scientific Methods
A. Characteristics of living things
B. Scientific Methods
C. Affixes and Roots
Part 1 – Characteristics of Living
Things
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Identify the 5 characteristics of life
Compare stimulus to response
Define homeostasis
Describe the differences between Type I
and II diabetes
What is biology?
• Biology is the study of life.
• This, of course, leads to the question…
What is life?
• After observing organisms, or living things,
scientists created a list of characteristics that
all living things have in common.
All living things…
are composed of one, or more
cells.
reproduce.
unicellular
multicellular
make babies.
grow.
get bigger.
respond to their environment.
react.
maintain homeostasis.
obtain and use energy
keep an internal
balance.
eat or make food.
adapt to their environment.
evolve.
All living things are composed of
one or more cells.
• The four amoebas
(top) and the euglena
(bottom), are each
made up of just one
cell each.
• Do they meet this first
requirement of living
things?
All living things reproduce.
• To reproduce, or make
more copies of
oneself, can be done
sexually. For
example, when two
giant pandas mate, a
baby panda bear can
be created.
All living things reproduce.
• Reproduction can also
occur asexually
(without sex), as in the
case of this cell which
is splitting into two
separate cells.
All living things grow.
• Some living things
not only grow
larger, but undergo
drastic physical
changes.
• The five images are
all of the same
insect in different
stages of life.
All living things respond to their
environment.
• A Stimulus (cause) =
triggers a response
(effect)
• Dr. Pavlov rang a bell
whenever he served
his dogs food. As a
result the dogs would
drool every time they
heard a bell; food or
no food. What was
the stimulus? What
was the response?
Dr. Pavlov gets treated.
Years later one of the dogs
sought therapy.
All living things maintain
homeostasis.
• Homeostasis = stable
internal body
conditions and
environment
– Temperature, pH,
fluid/mineral content,
etc
• Failure to maintain
homeostasis usually
leads to death
Diabetes
• The body releases a
hormone called
insulin from the
pancreas to maintain
blood glucose (sugar)
levels
• Diabetes is a
condition in which the
body’s ability to
maintain stable
glucose levels is upset
Type I and II Diabetes
Type I Diabetes
Type II Diabetes
• Body is unable to
produce insulin
• Usually diagnosed in
children
• Genetic; not caused by
diet
• Cells in the body no
longer respond to
insulin
• Usually occurs in adults
• Caused by obesity and
sugar rich diets
All living things obtain and use
energy.
• This cheetah will gain
energy from eating
this gazelle.
• What other examples
of energy obtaining do
you see?
All living things adapt to their
environment.
• The figure on the right
is not just of a tree
branch. If you look
closely there is an
insect there known as
the walking stick.
How is it adapted to
its environment?
All living things adapt to their
environment
• How do a duck’s feet
(top) differ from an
owl’s feet (bottom)?
• How do these
adaptations help each
to survive?
Summary Questions
1. What are the 5 characteristics of living
things?
2. A person feels cold and he shivers as a
result. Identify the stimulus and the
response.
3. Define Homeostasis and provide 2
examples.
4. Explain the difference between Type I and
Type II Diabetes
Part 2 – Scientific Method
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Lab Report
Independent vs. Dependent Variables
Experiment vs. Control groups
SI
What are scientific methods?
• The common steps that biologists and other
scientists use to gather information and
answer questions
The five basic steps
1. Identify a problem.
2. Formulate a hypothesis
3. Design an experiment.
4. Analyze the results.
5. Draw conclusions.
Identify a problem.
• Any question that can
be explored
scientifically via
observations or
experimentation is
valid.
• How do elephants
communicate?
• What effect will
special seeds have on
mice?
• Does a relationship
exist between cost and
absorption quality of
paper towels?
Formulate a hypothesis.
• A hypothesis is an explanation for a
problem or a question that can be tested.
• It’s your best guess as to what the results of
an experiment are going to be.
• Example: A direct relationship exists
between cost and amount of water a paper
towel can absorb.
Design an experiment.
• independent variable: what the scientist changes.
example: brand of paper towel
• dependent variable: what the scientist measures.
example: water volume absorbed
• control group: receives no experimental treatment.
example: a dry paper towel
• experimental group: receives experimental
treatment. example: three brands of paper towels
that the scientist wets.
Analyze results.
• Look at data tables
created during the
experiment. Make
graphs out of them to
better understand what
is going on.
Draw conclusions.
• Decide why you think
the results were what
they were.
• Example: Paper towel
brand X was thicker
and 2-ply, hence the
greater cost to produce
and also the greater
amount of material to
absorb water.
SI (metric units)
Length = meters (m)
Volume = liters (L)
Mass
= grams (g)
Unit
Meter
Metric
equivalent
1m
Examples
A little more than a yard
Kilometer
1,000m
About 2/3 of a mile
centimeter
0.01m
Radius of a penny
millimeter
0.001m
Width of a pencil tip
liter
1L
½ a pop bottle
milliliter
0.001L
About 15 drops of water
Summary
Part 3: Affixes and Roots
• Identify the meaning of words using affixes
How am I suppose to understand
all these big biology words?
• Affixes = prefixes and suffixes
• Prefixes are added to the beginning of a
word
• Suffixes are added to the end of a word
• Roots are the foundation of a word.
By familiarizing yourself with just a few of
these you can determine the meanings of
many biology terms.
Affixes and Roots
a
Without/not
anti
against
bi / di
two
bio
life
chlor
light green
meso
middle
cide
kill
Cyto
cell
genesis
to originate
homo/homeo
same
hetero
different
logy
study of
macro
large
micro
small
auto
self
chromo
color
multi
many
pro
before
uni
one
zoo
animal
zygous
two joined
aero
air
aqua
water
Terra/e
land
derm
Ecto
Endo
Epi
Hemo
Hyper
hypo
skin
outer
inner
Highest/above
blood
above
below
Summary Questions Part 3:
Derive the meaning
1. biology
2. zoology
3. unicellular
4. homozygous
5.antacid
6. microbiology