Themes of
Biology
Biology CPA
Miss Colabelli
Biology
 The
study of life
 Biologists study the smallest
organisms, like bacteria, to large
animals like elephants
 Many different types of biology
 Nutritional
 Micro
 Pathology
Characteristics of Life
 All
living things have similar qualities
 Broken down into 7 characteristics
of life
 Organization
 Response
to stimulus
 Homeostasis
 Metabolism
 Development
 Reproduction
 Evolution
Organization
 Degree
of order when an
organism’s internal and external
parts
 Each living organism is made of one
or more cells
 Cell  tissue  organ  organ
system  organism
Response to Stimuli
 Living
organisms have
the ability to respond to
a stimulus


Can be a physical
change
In response to the
environment
 Necessary
for an
organism to survive in
their environment and
stay alive
Homeostasis
 Organisms
must maintain
an internal balance
 Due
to environmental change
 Regulatory
system in order
to keep balance
 Body
temperature
 Salt intake and water intake
Metabolism
 Organisms
need to make energy
from their environment
 Humans
eat food in order to get energy
 Plants make their food from the sun and
water
Growth and Development
 All
living things grow and increase in
size
 Done by division and making new
cells
 Cell
division is when one cell is made
from a pre-existing cell
 Development
is the process of an
organism maturing into an adult
Reproduction
 Process
of living things producing
themselves
 Essential for continuing a species
 Some organisms lay eggs, some have a
baby grow internally
 The process of two organism passing their
DNA to its offspring is sexual reproduction
 Two parents  one or more organisms
 The process of one organism making an
identical copy of itself is asexual
reproduction
 One parent  2 daughter cell
Evolution
 Change
over time
 Populations of an
organism can
change based on
environmental
conditions
 Important for survival
in a changing world
Diversity & Unity of Life
All
living things have features
that are common
Tree of Life
Tree of Life
How
scientists organize
organisms into groups that are
similar to each other
Scientists believe we
descended from one common
ancestor (the roots)
Tree of Life
The
common ancestor
branched out into diverse
species
Organisms change due to their
environment
Three Domains of Life
Interdependence
Organisms
interacting with each
other
Ecology is the study of organisms
interacting with each other
When ecologists study organisms in a
specific environment it is called an
ecosystem
Ecosystem
Human Impact
Humans
have been on earth
for a very small amount of time
Our impact on the planet has
been drastic
Think of some environmental
changes humans have
caused…
Evolution of Life
Organisms
change over time
BUT their genetic characteristics
do not
Populations that change over
time is known as evolution
Misconceptions
Evolution
 Descent
with modification when
inherited traits within a population
 Small changes over a long period
of time that a new genetically
distinct new species can arise
 Tree of life is a symbol for this
evolution over time
Natural Selection
Organisms
that have
favorable traits are better
able to survive and pass on
their traits to next
generation
What do you see?
Black & Peppered Moths
Adaptation
Traits
that improve an
individuals ability to survive
White rabbit and short ears in
snowy place
The individuals that survive are
able to pass on traits to next
generation
Analyzing Graphics
 Would
you think that Archaea are more
closely related to Bacteria or Eukarya?
Review
Why
is evolution important in
helping explain the diversity of
life?
What is the difference between
evolution and natural
selection?
Make a hypothesis
 Fossil
evidence shows that bats descended from
shrewlike organisms that could not fly. Write a
hypothesis for how natural selection might have
led to flying bats.
Designing and Experiment
 Scientific
Method
 Observation
 Question
 Form
a hypothesis
 Experiment
 Data collection and
analysis
 Conclusion
Observation and Question
 Begins
with observing something in nature
 2 types of observation


Qualitative – using senses
Quantitative – measurement
 Wondering
how or what about it
 Ex:


Observation: Owls capture prey in the dark
Question: How do owls detect prey in the
dark?
Hypothesis
 Possible
answers for question in mind that
you can test with an experiment
 Educated guess of how something occurs
 Can be more than one
 Ex:



Owls hunt in the dark by vision
Owls hunt in the dark by hearing
Owls hunt in the dark by sensing body heat
Experiment


Design an experiment to test your hypothesis
Controlled experiment

Control group


Experimental group


What you are testing for
Independent variable


What you compare data to
What is being tested for (ex: presence or absence of
light)
Dependent variable

How the experiment responds (ex: if the owl can
catch its prey)
Collecting/Analyzing Data
 Collecting

Data
Usually quantitative data
 Compare
experimental results to
controlled results
 Analyzing Data


Compare results to other studies and refine
hypothesis
Create charts, graphs, tables to show data
Conclusion
 Either
supports or rejects your original
hypothesis
 If it supports

 If

Can move on to construct a theory with
research
it rejects
Refine and change hypothesis and create
new experiment