Transcript Classification

Introduction to Taxonomy
Differential Biology
6th Period
April 11, 2005
Taxonomy
Definition:
The discipline of describing and classifying
an organism.
7 levels of Taxonomy
Kingdom
Phylum
Class
Order
Family
Genus
Species
King
Philip
Came
Over
For
Green
Spaghetti
5 Kingdoms
Monera (bacteria)
Protista
Fungi
Plantae
Animalia
Cladograms
These are organized according to shared,
specialized characteristics.
Example:
In this sense birds are reptiles because the
two groups have many similar derived
characteristics.
Example of a Cladogram
Source: http://www.amnh.org/exhibitions/hall_tour/spectrum/non_flash_index.html
Three Domains
There is much debate about how many
domains there should be and what they
should include. Science has argued over
this for years. For our class we will use the
three most commonly accepted domains.
Three Domains Con’t
Archaea – bacteria that lives in extreme
habitats, possibly from primitive earth.
Eubacteria – All other prokaryotic
organisms.
Eukarya – All eukaryotic life.
Comparison of Domains
Characteristic
Eubacteria
ArchaeBacteria
Eukaryotes
Nuclear envelope
absent
absent
present
Organelles
absent
absent
present
Peptidoglycan cell
present
wall
absent
absent
Type of
membrane lipids
Some branched
hydrocarbons
Unbranched
hydrocarbons
Unbranched
hydrocarbons
Source: http://www.cas.vanderbilt.edu/bsci100/bacteria.viruses.htm
Characteristic
Eubacteria
RNA
One
polymerases
ArchaeBacteria
Eukaryotes
several
several
Initiator amino
acid
formylmethionine
methionine
Introns
Absent
present in some
genes
present
Response to
chloroamph
enicol
(antibiotic
that inhibits
protein
synthesis)
Sensitive
insensitive
insensitive
Source: http://www.cas.vanderbilt.edu/bsci100/bacteria.viruses.htm
methionine
A Brief Summary
What is taxonomy?
What was the acronym for the 7 levels of
taxa?
Who can list the 7 levels?
Why is there such a controversy over the
domains?
Something To Look Forward To
Tomorrow we are going to begin
working on what is called a dichotomous
key. It’s sort of like creating a map
for identifying organisms.