1. Classification & Taxonomy 10-1 An organized system to classify all living things

2. Biology is the study of life… But how do we know something is “alive”? –Metabolism Consume molecules Produce wastes Exchange gases –Reproduction –Cells –DNA

3. The Need for a Classification System… Organizing and categorizing all of the organisms that exist on earth today is quite a task! A system of classification must be… - organized and logic - universal (used by all scientists) Our current system breaks down organisms into more & more closely-related groups until only one group is left…the “species”!

4. Taxonomy… Taxonomy is the study, practice, and science of the classificiation of organisms.

5. Binomial Nomenclature (“to name with 2 names”) Each species is named with 2 words –The first word is the “genus” –The second word is the “specific epithet” –When written together, this name is called the “species” –Ex: Homo sapiens or Homo sapiens Homo = genus of humans sapiens = specific epithet of humans Note: genus is capitalized, other is not…both underlined or italicized

6. Taxons Groups of related genera are classified together in the same family Groups of related families for an order This follows the pattern… Orders  Class  Phylum  Kingdom We usually memorize these from the largest to smallest direction: –K  P  C  O  F  G  S

7. Test Yourself! Name the 7 major taxons in order… Kingdom Phylum Class Order Family Genus Species

8. Dichotomous Keys Rules: –Always start at clue set #1 –One of the choices must be correct…the other must be incorrect –Identify the correct one and go where it says –When creating a key, it is better to use “is…is not” format for clues –Will always have one fewer clue than # of objects

9. Dichotomous Key Example Example: 1. A. contains ink……………..…..go to 2 B. does not contain ink………..go to 3 2. A. point made of metal………..pen B. point not made of metal……marker 3. A. made of plastic…..mechanical pencil B. not made of plastic…...regular pencil

10. All organisms have been placed into one of 6 kingdoms. This is a generally agreed-upon standard, but is subject to change We have not always had 6 kingdoms, and some scientists use fewer or more What criteria are used to place an organism in a kingdom?

11. Basic Criteria for Kingdoms (The Big 5!) 10-2 # of Cells –Unicellular or Multicellular Type of Cell –Prokaryotic or Eukaryotic Cell Wall –Yes or No Nutrition –Autotrophic or Heterotrophic Motility –Yes or No

12. Test Yourself! What do the following mean? Unicellular Multicellular Prokaryotic Eukaryotic Autotrophic Heterotrophic Motile Nonmotile Cell Wall

13. Bacteria K. Archaebacteria –Harsh environments –Methanogens (anerobic) –Thermophiles (high heat) –Halophiles (salt) K. Eubacteria –“common” bacteria –Ex: E.coli; Staphylococcus aureus The Big 5: –Unicellular –Prokaryotic –The other 3 traits are variable… examples of bacteria exist for each trait

14. K. Protista The most diverse and oft-changing kingdom! The Big 5: –Unicellular*** –Eukaryotic –The other 3 traits are variable…protists of various types exhibit both versions.

15. K. Fungi Often seem plant-like…but cannot make food! The Big 5: –Multicellular –Eukaryotic –Cell wall – of chitin –Heterotrophic – absorb food –Nonmotile

16. K. Plantae Usually green due to chlorophyll The Big 5: –Multicellular –Eukaryotic –Cell wall – of cellulose –Autotrophic –Nonmotile

17. K. Animalia Large, motile creatures that eat! The Big 5: –Multicellular –Eukaryotic –No cell wall –Heterotrophic – ingest food –Motile

18. Taxonomic Tree 10-3 Cladistics- classification system based on phylogeny; assumes that as groups of organisms diverge and evolve from a common ancestral group, they retain derived traits. Cladogram is the diagram used to represent the phylogeny of a species based on those derived traits.

19. Taxonomic Tree Which group of organisms are most closely related? Butterflies, moths and flies

20. X Y Z 1.A. Is multicellular………………………………..go to 2 B. Is unicellular……………………….…………go to 3 2.A. Contains chlorophyll; is green…………….Chlorella B. Contains erythrophyll; is red………………Hemalia 3.A. Cell is oblong with tiny cilia………………...Paramecium B. Cell is blob-like with slender extensions….Amoeba