Classification
Chapter 18
Taxonomy
The field of biology
that deals with
classifying organisms.
Each level is called a
Taxon.
How do Taxonomists classify?
1. Physical Structures
2. Embryological Development
3. Chemical Processes
4. DNA
There are 8 major levels for
classification!
Organisms within each category are:
more closely related as you move from the domain
toward the species level!
Species
Recall… a species is a group
of organisms that share most
characteristics and can
interbreed to produce fertile
offspring.
Domains are:
The largest groups in the modern classification system. There
are 3 domains shown above.
The next level
down from domain
is…
Kingdom
Domain
Bacteria
Kingdom
Eubacteria
Archaea
Archaebacteria
Eukarya
Protista
Fungi
Plantae
As shown above, each domain
includes:
1 or more kingdoms of organisms
Animalia
Domain
Bacteria
Kingdom
Eubacteria
Archaea
Archaebacteria
Eukarya
Protista
Fungi
Plantae
The domain Bacteria is
made up of:
1 Kingdom: Eubacteria “true bacteria”
Animalia
Recall that bacteria:
are single celled prokaryotes. Their cell walls
contain a substance called peptidoglycan
Domain
Bacteria
Kingdom
Eubacteria
Archaea
Archaebacteria
Eukarya
Protista
Fungi
Plantae
The domain Archaea also
contains:
1 kingdom, archaebacteria.
Animalia
The cell walls of archaea DO NOT
contain Peptidoglycan.
Archaea live in extreme environments like thermal
vents and salt lakes.
Domain
Bacteria
Kingdom
Eubacteria
Archaea
Archaebacteria
Eukarya
Protista
Fungi
Plantae
The domain Eukarya contains
4 kingdoms:
Protista (protists), Fungi, Plantae (plants),
and Animalia (animals)
Animalia
All members of the Eukarya
Kingdom are eukaryotes!
“Autotrophs - Organism that makes its own food
Heterotroph - Feeds on other organisms.”
–Johnny Appleseed
Kingdoms in the Domain Eukarya
Kingdom
Characteristics
Examples
Protista
Unicellular or Multicellular, nucleus, plasma membrane.
May have a cell wall and chloroplasts, includes
heterotrophs and autotrophs.
Euglenas, algae,
paramecia, amoebas
Fungi
Unicellular or multicellular, has a nucleus,
plasma membrane, and cell wall. Only
heterotrophs.
Yeasts, mushrooms,
molds, mildews
Plantae
Multicellular, nucleus, plasma
membrane, cell wall, chloroplasts. Only
autotrophs.
Mosses, ferns, trees,
grasses
Animalia
Multicellular, nucleus, plasma
membrane, no cell wall or chloroplasts,
only heterotrophs.
Sponges, worms, insects, fish,
amphibians, reptiles, birds,
mammals
Kingdoms are divided into Phyla or
Phylum
Phyla are subdivided into classes, then orders,
family, genera, and species.
Binomial Nomenclature
Giving each organism a 2 part name
First part of name
is genus:
This includes
related species
Second part of
name identifies
the organism’s
species
Binomial Nomenclature was created by:
A swedish botanist in the 1700’s: Carolus Linnaeus
Phylogeny
Evolutionary history of a group of organisms.
Scientists show the
development of
groups of organisms
from a common
ancestor in branching
diagrams called
Phylogenetic Trees.
Evolutionary Relationships can also
be shown through:
Cladograms
Dichotomous
Keys
A tool that can be used to
determine the identity of
something by matching
observations to a series of
paired statements or
questions.