1. Classification I: Intro
IB Biology

2. Classifying Organisms
The science of classifying organisms is called taxonomy
The “father of modern taxonomy” was Carolus Linnaeus (Carl von Linné)
Organisms are grouped into “taxa” based on their similarities to each other

3. The Old System 5 Kingdom Classification System:
Monera: all prokaryotes
Protista: single-celled eukaryotes (protists)
Fungi: multi-cellular heterotrophic sessile eukaryotes
Plantae: multi-cellular autotrophic sessile eukaryotes
Animalia: multi-cellular heterotrophic motile eukaryotes

4. The New System 3 Domain System: Archaea: prokaryotes; extremophiles
Eubacteria: prokaryotes; true bacteria
Eukarya: eukaryotes
Protista
Fungi
Plantae
Animalia

5. Under Domain and Kingdom
Organisms are grouped into smaller and smaller groups all the way down to their species
A species is the most specific grouping and includes only organisms that can interbreed with each other and produce fertile offspring
To remember the grouping order – just remember:
King Philip Came Over For Gold Specks

6. King Philip Came Over For Gold Specks
Classification Taxa
King Philip Came Over For Gold Specks
Kingdom
Phylum
Class
Order
Family
Genus
Species
Note: Scientific names are always written with the first letter of the genus capitalized, the first letter of the species lower-case, and the whole thing underlined in italics.
Together, these make up a species’ scientific name
Example: Ursus americanus
Common Name: American Brown Bear

7. Domain Archaea Formerly part of the kingdom monera
Microbiologists who study bacteria determined that the DNA of these are much different from other, true bacteria
Most Archaea live in extreme conditions (very hot, acidic/basic, sulfurous, etc)

8. Domain Eubacteria Formerly a part of the kingdom monera
Name means “true bacteria”
These are the kind of bacteria likely to make us sick, live in our gut to help us digest food, or be used in the making of cheese

9. Domain Eukarya
Contains all of the eukaryotes (organisms with a nucleus in their cells)
Protista
Fungi
Plantae
Animalia

10. Kingdom Protista Includes All Protists:
Eukaryotic
Unicellular
Animal-Like Protists (protozoans)
Pseudopods, Ciliates, Flagellates
Examples: Amoeba, Paramecia, Giardia
Plant-Like Protists (autotrophic)
Euglenoids, Dinoflagellates, Diatoms, Green/Red/Brown Algae
Fungus-Like Protists
Examples: Water molds, slime molds

11. Kingdom Protista Animal-Like (Protozoans) Fungus-Like Plant-Like
Paramecium
Giardia
Amoeba
Fungus-Like
Plant-Like
Water Mold
Slime Mold
Diatom
Euglena
Green Algae
Brown Algae
Dinoflagellates

12. Kingdom Fungi
All eukaryotic, multicellular, heterotrophic, sessile organisms
Includes: molds, mushrooms, rusts, lichens
Mycorrhizal associations allow plants to absorb more water and nutrients from the soil

13. Kingdom Plantae
All eukaryotic, multicellular, autotrophic, sessile organisms
Produce their own food from sunlight and carbon dioxide
Common Phyla:
Bryophyta (mosses)
Pteridophyta (ferns)
Coniferophyta (conifers, like pine trees)
Angiospermophyta (angiosperms, like flowering plants

14. Coniferophytes (Pine Trees)
Kingdom Plantae
Primitive Plants
Bryophyte (Moss)
Pteridophyte(Fern)
Complex Plants
Pteridophyte(Fern)
Coniferophytes (Pine Trees)
Angiosperm; Dicot
Angiosperm; Monocot

15. Kingdom Animalia
All eukaryotic, multicellular, heterotrophic, motile (most) organisms
Common Phyla:
Chordata (those with spinal chords)
Annelida (worms)
Mollusca (inc. clams, oysters, etc..)
Arthropoda (crustaceans, insects, spiders)
Porifera (sponges)
There are about 40 such Phyla

16. Human Classification Domain Eukarya Kingdom Animalia Phylum Chordata
Class Mammalia
Order Primate
Family Hominidae
Genus Homo
Species Sapien

17. Dichotomous Keys Used to help identify unknown specimen
Work by asking yes or no questions whose answers lead the reader to the correct taxa for the organism
Simple Example:
1a. Organism has 4 legs Go to # 2
1b. Organism has more than 4 legs Go to # 20
2a. Organism has a tail Go to # 3
2b. Organism has no tail Go to # 35
3a. Organism has stripes Bengal Tiger
3b. Organism has no stripes African Lion

18. Dichotomous Key Try this one:
1a. Organism walks on all 4 legs (quadruped) 2
1b. Organism walks on 2 legs (biped) 8
2a. Organism has visible fur 3
2b. Organism has no visible fur
3a. Organism lives in warm climates 7
3b. Organism lives in cold climates 4
4a. Organism has brown or black fur Ursus Americanus
4b. Organism has white fur Ursus Maritimus