Characteristics of Life and Classification Illustrative
Dictionary
Biology: is the study of living things
or organisms.
DNA: Stores and transmits genetic
information. Universal genetic Code.
All living things have the ability to
If you are interested in learning more pass on their genetic material (DNA)
to their offspring.
about living things, then you should
study biology.
Organization: living things are
arranged from the simplest to most
complex.
In biology, living things are organized
from the simplest to most complex:
atom, molecule, cell, tissue, organ,
organ system, organism, population,
communities, ecosystem, and
biosphere.
Growth: increase in size or number
of cells.
All living organisms grow and develop.
Stimulus Response: internal or
external factor in the environment
that causes a response: temperature,
light, sound, pain, hunger….
When I was taking the cookies out of
the oven my hand touched the hot
oven accidently and I responded by
pulling my hand away quickly.
Sexual Reproduction: reproduction
that involves an egg and a sperm. (2
parents)
In sexual reproduction, two parents
contribute genetic info (DNA) to
produce a unique offspring.
A population depends on
reproduction to continue the
species.
Asexual Reproduction: reproduction
which the offspring comes from a
single organism; inherit traits from
one parent.
Metabolism (energy): The
breakdown of molecules to obtain
energy.
Asexual reproduction is the primary
form of reproduction for singlecelled organisms such as
archaebacteria, eubacteria, and
protists.
When my body breaks down the
cheeseburger I had for dinner, it
will give me energy to study for my
biology quiz.
Adaptation (trait): a change in an
organisms DNA that increases their
chance of survival.
A cactus has an adaptation that
allows it to survive the hot desert
heat by not losing water very easily.
Unicellular: is an organism that
consists of only one cell.
Bacteria is an example of an organism
that is made up of one cell, it is a
unicellular organism.
Multicellular: an organism that
consists of more than one cell.
Plants, animals, fungus, and most
protists are multicellular, or manycelled.
Homeostasis: is the ability to
maintain internal stability in an
organism to compensate for
environmental changes.
When I get too hot, my body will
begin to sweat to help me maintain
homeostasis.
Autotroph: is an organism that
produces its own food.
I can make my
own food!!
Plants, cyanobacteria, and algae are
autotrophs because they can use the
sun to make their own food.
Prokaryotes: organisms that DON’T
have a nucleus.
Heterotroph: cannot make their own
food, they have to get their energy
from an outside source.
Organisms like this bear are
heterotrophs, they cannot make
their own food, they get energy
from an external source.
Eukaryotes: organisms that DO have
a nucleus.
NUCLEUS
NUCLEUS
Eubacteria and Archaebacteria are
examples of prokaryotes.
Animals, plants, fungi, and protest
are examples of eukaryotes.
Classification
 3 Domains: Eukarya, Archaea, Bacteria
 6 Kingdoms: Plantae, Fungi, Animalia, Protista, Eubacteria (everyday
bacteria), Archaebacteria (ancient bacteria, live in extreme conditions)
 7 levels of Taxonomy
o Kingdom (Largest)
o Phylum
o Class
o Order
o Family
o Genus
o Species (Smallest)