Chapter 1
The Scope of Biology
Section 2: Biology explores life in its
diverse forms
Section 3: Ten themes unify the study
of life
Life’s Diversity of Species

The earth is full of a diverse # of plants and
animals.
 Each
different kind of organism is an example of a
different species.
– Definition: distinct form of life
Classifying Life Into Domains

In classifying, we call the largest category a
domain.
– Definition: broadest category used to classify life
forms
 Three main domains  DOMAIN ARCHAEA, DOMAIN
BACTERIA and DOMAIN EUKARYA
 DOMAIN EUKARYA is broken down into 4
sub categories
Kingdom Protista, Kingdom Fungi,
Kingdom Plantae, Kingdom Animalia
Three Domains of Life
Archaea
Bacteria
Eukarya
Very tiny
Unicellular
Lack nuclei
Prokaryotic
Very tiny
Unicellular
Lack nuclei
Prokaryotic
Includes:
protists, fungi,
plants, and animals
Multicellular
Contain nuclei
Eukaryotic
Chapter 1
The Scope of Biology
Section 2: Biology explores life in its
diverse forms
Section 3: Ten themes unify the
study of life
Biological Systems

Two main types of biological systems
– Your body and the body of all living beings
(organisms) is made up of different systems
working together and interacting with each other.
– An ecosystem has properties that depend on how
its parts interact.
The Cellular Basis of Life

ALL ORGANISMS ARE MADE UP OF CELLS
 Single
cell
Tissue
Organ
Organ
System
Form and Function

How something works is related to its structure 
form fits function
Reproduction and Inheritance

Each species will recreate offspring with members
within it’s own species
 Genes
are responsible for the passing on of traits and
physical characteristics
 Genes are found within the DNA of each cell
Interaction With the Environment

As part of an ecosystem, each organism interacts
continuously with its environment.
 Photosynthesis:
process by which the plants use the
sun’s energy to convert water and carbon dioxide
into sugars
Energy and Life
 All
of life’s functions require the use
of energy
 Energy
is found all around us and within our
bodies and environments.

Photosynthesis 
plants convert light energy to
chemical energy stored in sugars and other foods.
– Plants are examples of producers.
 Definition: organism that makes its own food
(autotroph) and produces organic molecules
that serve as food for other organisms in its
ecosystem
– Organisms that feed on the producers are
called consumers.
 Definition: organism that obtains food by
eating producers and other consumers
Regulation


Regulation is the ability of organisms to regulate
their internal conditions.
When the internal environment of an organisms
is in a “steady state” despite changes in the
external environment, the body is said to be in
homeostasis.
– EXAMPLE: if your internal “thermostat” in your brain detects a
slight rise in body temperature on a hot day, your brain signals
your skin to produce sweat – sweating helps cool your body.
Adaptation and Evolution

Adaptations are found throughout generations of
species.
 Definition:
inherited characteristic that improves
an organism’s ability to survive and reproduce in a
particular environment

Organisms adapt to their environments
because of the variation among individuals is
a population.
 Definition:
group of individuals of the same species
living in a particular area at the same time
– If a particular variation is helpful, individual
with the variation may live longer and
produce more offspring than those that do
not have it. (this is called natural selection)

Natural selection is the mechanism by which
evolution occurs.
 Definition:
generation-to-generation change in the
proportion of different inherited genes in a
population that account for all of the changes that
have transformed life over an immense time
Biology and Society

The application of biology in society has made
major impacts on daily life.
– EXAMPLES: research on the nervous system is
improving the treatment of some mental illnesses,
water and air pollution are changing the way
people thing about their relationship to the
biosphere, etc.
Scientific Inquiry

Scientists (over many years) have asked
questions about the natural world.
– These questions have led us to the knowledge we
have today and continue to inspire us to solve what
we do not know.