1. Classifying Organisms
Ch.1 Sect 2

2. Classifying Living Things
Aristotle was one of the first people to classify organisms.
He classified organisms into 2 groups: plants or animals.
Classification: putting organisms into groups
Taxonomy: the science of classifying, naming, or describing organisms based on similar characteristics.
Classifying Living Things

3. 7 Levels of Classification
Kingdom
Phylum
Class
Order
Family
Genus
Species
King Philip Came Over For Grape Soda
Carolus Linnaeus classified organisms based on similar structures.
Placed organisms into 2 main group called Kingdoms
7 Levels of Classification

5. Robert Whittaker later proposed 5 kingdom system on classifying organisms.
If a new organism is discovered and does not fit any other kingdom, scientists will start a new kingdom.
6 Kingdoms:
Animalia- ex. Dog
Plantae – ex. sunflower
Archaebacteria- methane making bacteria.
Eubacteria – ex. strep
Fungi - mushroom
Protista – last kingdom discovered
Determining Kingdoms

7. Determining Domains Classification system is not complete.
Systematics- current classification system being used. (uses all characteristics to place organisms in the correct kingdom).
Kingdoms are now placed into 3 domains:
1. Bacteria
2. Archaea
3. Eukarya
Determining Domains

8. Scientific Names All organisms have a common name and scientific name.
The scientific name of an organism consists of the genus and species.
Binomial Nomenclature- is the naming system used to name organisms.
Species- a group of organisms that have similar traits and are able to produce a fertile offspring.
Genus- is a group of similar species.
Scientific Names

9. Dichotomous Keys- a series of descriptions arranged in pairs that leads the user to the identification of an unknown organism.
Cladograms – a branched diagram that shows the relationships among organisms including common ancestors.
Each branch in a cladogram follows a new characteristic.
Classification Tools