1. Classification of Living Things
D K P C O F G S
Classification of Living Things

2. Taxonomy
The practice of classifying plants and animals according to their presumed natural relationships.

3. Domains (3) This old system includes Domains
1. Archaea: ancient bacteria that can exist in extreme environments
2. Bacteria: the kind we know of today
3. Eukarya: includes all eukaryotes (protista, fungi, plantae, and Animalia)

4. What is classification?
Classification is the grouping of living organisms according to similar structures and functions.

5. Early classification systems
Aristotle grouped animals according to the way they moved

6. Characteristics of the Domains
Bacteria
Archaea
Eukarya
Cell Type
prokaryote
eukaryote
Number of Cells
Unicellular
unicellular
Uni and multicellular
Nutrition
Auto/heterotroph
Both
Number of Kingdoms
One
Four

7. The modern classification system :
Developed by Carolus Linnaeus
Consists of 7 levels:
Kingdom
Phylum
Class
Order
Family
Genus
Species

8. Helpful way to remember the 7 levels
King Philip Came Over For Good Soup.
King Philip Came Over For Green Skittles.

9. Levels of Classification
Kingdom: based on how organisms obtain food, types of cells, and the number of cells.
Phylum: physical similarities (this suggest a common ancestry)
Class: organisms have more in common (ex. mammals drink mils as babies)

10. Levels of Classification
Order: dichotomous keys (a checklist of characteristics)
Family: more in commons, so much so, that they are said to be related
Genus: the generic name is determined (1st part of the organisms scientific name)-very specific

11. Levels of Classification
Final and Lowest Level
Species: the most specific you can get.
Main Criteria: the ability to breed with similar organisms
(2nd part of the scientific name)

14. Binomial Nomenclature
Developed by Carolus Linnaeus
Two-name system:
First name is the organism’s genus
Second name is the organism’s species

15. What rules are used to write scientific names?
The first letter of the genus is ALWAYS capitalized
The first letter of the species is NEVER capitalized
Scientific names of organisms are always italicized or underlined

16. Using the Classification System
Field guides help identify organisms. -they highlight differences between similar organisms (like trees) Taxonomic Key (Dichotomous Key) -paired statements that describe the physical characteristics of different organisms

17. What steps would you use to identify a peach?
Taxonomic Key
1a Fruits occur singly Go to 3
1b Fruits occur in clusters of two or more Go to 2
2a Fruits are round Grapes
2b Fruits are elongate Bananas
3a Thick skin that separates easily from flesh Oranges
3b Thin skin that adheres to flesh Go to 4
4a More than one seed per fruit Apples
4b One seed per fruit Go to 5
5a Skin covered with velvety hairs Peaches
5b Skin smooth, without hairs Plums
What steps would you use to identify a peach?