1. Chapter 17: The Tree of Life

2. Section One: The Linnaean System of Classification
Taxonomy
The science of naming and classifying organisms
Developed by Carolus Linnaeus
Taxon: a group of organisms in the same classification system
Involves binomial nomenclature
Binomial nomenclature: a system that gives each species a two part scientific name using Latin
Gives a genus (first name) and a species name (second name)
Genus: includes one or more physically similar species that are thought to be closely related
Ex: Homo sapiens

3. Section One: The Linnaean System of Classification
Taxonomy
Has 7 levels of classification
Each level gets more exclusive
Kingdom
Phylum
Class
Order
Family
Genus
Species

4. Section Two: Classification Based on Evolutionary Relationships
Cladistics
Classification based on common ancestry
Phylogeny: the evolutionary history for a group of species
Cladogram: an evolutionary tree that proposes how species may be related to each other through common ancestors
Derived characters: traits that differ in structure or function from that found in the ancestral line for a group of species

6. Section Two: Classification Based on Evolutionary Relationships
Species Relatedness
DNA sequencing can reveal whether or not two species are related
This has led to some species named being changed since they were first compared only by physical characteristic and not if their DNA was similar

7. Section Four: Domains and Kingdoms
Tree of Life
A model that shows the most current understandings of how living things are related
There are currently 6 kingdoms and 3 domains
The 3 domains are
Bacteria
Archae
Eukarya

8. Section Four: Domains and Kingdoms
Bacteria
Single celled prokaryotes
One of the largest groups of organisms on Earth

9. Section Four: Domains and Kingdoms
Archae
Single celled prokaryotes
But have different cell walls than bacteria
Can live in extreme environments like deeps sea vent and the mouths of volcanoes

10. Section Four: Domains and Kingdoms
Eukarya
All organisms with eukaryotic cells
Have a nucleus and organelles
Can be single or multicellular
Includes the kingdoms Protista, Plantae, Fungi, and Animalia