1. Classification

2. Species of Organisms There are 13 billion known species of organisms
This is only 5% of all organisms that ever lived!!!!!
New organisms are still being found and identified

3. What is Classification?
Classification is the arrangement of organisms into orderly groups based on their similarities
Classification is also known as taxonomy
Taxonomists are scientists that identify & name organisms

4. Benefits of Classifying
Accurately & uniformly names organisms
Prevents misnomers such as starfish & jellyfish that aren't really fish
Uses same language (Latin or some Greek) for all names
Sea”horse”??

5. Confusion in Using Different Languages for Names

6. Latin Names are Understood by all Taxonomists

7. Early Taxonomists 2000 years ago, Aristotle was the first taxonomist
Aristotle divided organisms into plants & animals
He subdivided them by their habitat ---land, sea, or air dwellers

8. Early Taxonomists
John Ray, a botanist, was the first to use Latin for naming
His names were very long descriptions telling everything about the plant

9. Carolus Linnaeus 1707 – 1778 18th century taxonomist
Classified organisms by their structure
Developed naming system still used today

10. Carolus Linnaeus Called the “Father of Taxonomy”
Developed the modern system of naming known as binomial nomenclature
Two-word name (Genus & species)

11. Standardized Naming Binomial nomenclature used Genus species
Latin or Greek
Italicized in print
Capitalize Genus, but NOT species
Underline when writing
Turdus migratorius
American Robin

12. Binomial Nomenclature

13. Rules for Naming Organisms
The International Code for Binomial Nomenclature contains the rules for naming organisms
All names must be approved by International Naming Congresses (International Zoological Congress)
This prevents duplicated names

14. Classification Groups
Taxon ( taxa-plural) is a category into which related organisms are placed
There is a hierarchy of groups (taxa) from broadest to most specific
Domain, Kingdom, Phylum, Class, Order, Family, Genus, species

15. Hierarchy-Taxonomic Groups
Domain
Kingdom
Phylum
Class
Order
Family
Genus
Species  most specific
BROADEST TAXON
Genus and species are the two names used to identify specific organisms in the binomial system of classification. Division is used for plants.

16. Did Do
King Kids
Phillip Prefer
Come Candy
Over Over
For Fried
Good Green
Soup?Spinach?

18. Domains Broadest, most inclusive taxon Three domains
Archaea and Eubacteria are unicellular prokaryotes (no nucleus or membrane-bound organelles)
Eukarya are more complex and have a nucleus and membrane-bound organelles

19. Sewage treatment plants, thermal vents, etc.
Archaea live in harsh environments and may represent the first cells to have evolved.
Sewage treatment plants, thermal vents, etc.

20. Many bacteria are important environmentally and commercially.
Eubacteria, some of which cause human diseases, are present in almost all habitats on Earth.
Live in the intestines of animals
Many bacteria are important environmentally and commercially.

21. Domain Eukarya is Divided into Kingdoms
Protista (protozoans, algae…)
Fungi (mushrooms, yeasts …)
Plantae (multicellular plants)
Animalia (multicellular animals)

22. Protista Most are unicellular Some are multicellular
Some are autotrophic, while others are heterotrophic
Junk drawer of classification

23. Fungi Multicellular, except yeast
Absorptive heterotrophs (digest food outside their body & then absorb it)
Cell walls made of chitin

24. Plantae All Multicellular Autotrophic
Absorb sunlight to make glucose – Photosynthesis
Cell walls made of cellulose
Growth, with increases in size and number of cells, is part of development.
Development involves many stages from conception until death.

25. Plants can be Gymnosperms or Angiosperms
Plantae
Plants can be Gymnosperms or Angiosperms
Gymnosperms=seeds without covering=naked
Angiosperms= Covered seeds/ flowering plants
Growth, with increases in size and number of cells, is part of development.
Development involves many stages from conception until death.

26. Animalia All Multicellular
Ingestive heterotrophs (consume food & digest it inside their bodies)
Feed on plants or animals

28. Phylogenic Species Concept
Phylogeny is the evolutionary history of a species.
A phylogenetic tree is a graphical representation of the evolutionary relationship between taxonomic groups.
The phylogenic species concept defines a species as a cluster of organisms that is distinct from other clusters and shows evidence of a pattern of ancestry and descent.
Organisms can also have derived traits– traits not present in ancestors

30. Taxons
Most Genus contain a number of similar species, with the exception of Homo that only contains modern humans
Classification is based on evolutionary relationships

32. Basis for Modern Taxonomy
Homologous structures (same structure, different function)
Similar embryo development
Similarity in DNA, RNA, or amino acid sequence of Proteins

33. Homologous Structures show Similarities in mammals.

34. Analogous structures can be used for the same purpose and can be superficially similar in construction, but are not
inherited from a
common ancestor.
Show that functionally similar features can evolve independently in similar environments

35. Similarities in Vertebrate Embryos

36. Molecular Clocks
A molecular clock is a model that is used to compare DNA sequences from different species to estimate how long the species have been evolving since a common ancestor.
The differences between the genes indicate the presence of mutations.
The more mutations that have accumulated, the more time that has passed since divergence.

37. Cladogram
Diagram showing how organisms are related to a common ancestor based on shared, derived characteristics such as feathers, hair, or scales

38. Primate Cladogram

39. Dichotomous Keying Used to identify organisms
Physical Characteristics given in pairs
Read both characteristics and either go to another set of characteristics OR identify the organism

40. Example of Dichotomous Key
1a Tentacles present – Go to 2
1b Tentacles absent – Go to 3
2a Eight Tentacles – Octopus
2b More than 8 tentacles – 3
3a Tentacles hang down – go to 4
3b Tentacles upright–Sea Anemone
4a Balloon-shaped body–Jellyfish
4b Body NOT balloon-shaped - 5

41. Viruses
A virus is a nonliving strand of genetic material within a protein coat (capsid)
Virus DNA/RNA must be injected into host
No organelles to take in nutrients or use energy
Cannot move
Cannot replicate on their own

42. Viral Reproduction
1. Lytic Cycle- Virus is reproduced by host so quickly that the host cell breaks up and releases the virus/Active (FLU & Colds)
2. Lysogenic cycle- virus DNA joins the host DNA, the Host cell now has the virus embedded in it DNA and all of the cells the host makes will have the virus inside it. (Dormant)
The host will always have this virus. (Herpes, AIDS & Chicken Pox)

43. Viruses Common viruses include:
Human Immunodeficiency Virus(HIV) – causes AIDS
Common Cold– caused by virus
Influenza Virus – causes the flu