Classification
Why do Scientists Classify?
• The process of grouping things based on
their similarities is classification.
• Biologists classify so that organisms are
easy to study.
• The scientific study of how living things are
classified is called taxonomy.
• Knowing the classification levels of an
organism gives scientists a lot of
information.
Levels of Classification
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Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species
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Dear
King
Phillip
Came
Over
For
Good
Spaghetti
The naming system of Linnaeus
• Linnaeus placed organisms into groups
based on their observable features
(physical characteristics).
• Binomial nomenclature is a system that
gives each organism a two part name.
• Scientific names
– Written in italics and are in Latin.
– Based on the organism’s Genus and Species
Domains and Kingdoms
• Three domains of living things
– Bacteria
– Archaea
– Eukarya
• Organisms are placed into domains and
kingdoms based on their
– Types of cells
– Ability to make food
– Number of cells in their bodies
Domain Eukarya
• Includes Plants, Animals, Protists and Fungi
• Organisms in this domain are Eukaryotes; their
cells contain a nucleus
• Protists can be either unicellular or multicellular
• Mushrooms, molds, mildew, and yeast are all
fungi
• Plants are autotrophs; they can make their own
food.
• Plants and Animals are all multicellular
Domains Archaea and Bacteria
• Domain Archaea
– Contains Kingdom Archaebacteria
– Bacteria that live in extreme environments
• Domain Bacteria
– Contains Kingdom Eubacteria
– Bacteria that can be found anywhere
– Most are not harmful
Dichotomous Keys
 A dichotomous key is a tool that allows the
user to determine the identity of items in
the natural world based on the items
characteristics
 "Dichotomous" means
“divided into two parts” Greek origin
 dichotomous keys always give two distinct
choices in each step, often they are opposites
Black/white; good/evil; pointed/rounded
Let’s practice making a
dichotomous key with the
random objects you have
brought from your locker!
Fishbowl:
Have each student write at least one
question down about what they have
learned today, or a question about what
they still don’t understand. Put them all
into a bowl together. Have each student
draw out the card. Have students read
aloud and answer each other’s questions