1. Chapter 17 BIOLOGY

2. HOW WOULD YOU CATEGORIZE THESE?

3. THE HISTORY OF CLASSIFICATION Early Systems of Classification Classification – the grouping of objects or organisms based on a set of criteria Aristotle’s System Aristotle 394-322 BC Developed first widely accepted system of biological classification Based on the presence or absence of “red blood”

4. Linnaeus’s System Carolus Linnaeus 1707-1778 Broadened Aristotle’s system and formalized it to a scientific system Based off of observational studies of the morphology and the behavior of organisms Used taxonomic organization Taxonomy – a discipline of biology primarily concerned with identifying, naming, and classifying species based on natural relationships

5. BINOMIAL NOMENCLATURE Based on Linnaeus’s system Binomial Nomenclature – gives each species a scientific name that has two parts First part – genus name Second part – specific epithet or specific name that identifies the species Based on Latin Latin is a language that doesn’t change Historically is the language of science and education

6. BINOMIAL NOMENCLATURE Follows these rules: First letter of genus name always is capitalized; the rest of the genus name and all letters of the specific epithet are lower case If scientific name is written in a printed book or magazine, it should be italicized When a scientific name is written by hand, both parts of the name should be underlined After the scientific name has been written completely, the genus name often will be abbreviated to the first letter in later appearances. Ex. Cardinalis cardinalis can be written later as C. cardinalis

7. TAXONOMIC CATEGORIES Species and genus Taxon – a named group of organisms (pl. taxa) Genus – a group of species that are closely related and share a common ancestor Family – the next higher taxon, consisting of similar, related genera Higher Taxa Order – contains related families Class – contains related orders Phylum – contains related classes (division is used instead of phylum for bacteria and plants) Kingdom – contains related phyla Domain – the broadest of all taxa; contains related kingdoms

8. TAXONOMIC CATEGORIES

9. MODERN CLASSIFICATION Determining Species (See Table 17.2 p.491) Typological Species Concept Based on how a certain species looks Biological Species Concept Introduced by Theodosius Dobzhansky and Earnst Mayer Species are able to interbreed and produce fertile offspring Phylogenetic Species Concept Based on the Biological Species Concept and adds the natural history of a species based on ancestry Phylogeny – the evolutionary history of a species

10. CHARACTERS Characters are inherited features that vary among species Morphological Characters Birds and mammals – do not appear related yet according to evolutionary history, they are Biochemical Characters The use of biological molecules to show differences and similarities between species Used nucleotides and amino acids. Especially DNA and RNA

11. Molecular Clock is a model that is used to compare DNA sequences from two different species to estimate how long the species have been evolving since they diverged from a common ancestor A Cladogram is a branching diagram that represents the proposed phylogeny or evolutionary history of a species or group

12. DOMAINS AND KINGDOMS Grouping Species (Table 17.3 p.502) Domains are the broadest category in classification Three Domains: Bacteria Archaea Eukarya Within the Domains are Six Kingdoms: Bacteria, Archaea, Protists, Fungi, Plantae, and Animalia

13. DOMAIN BACTERIA Prokaryotes whose cell wall contain peptidoglycan Can survive many different environments

14. DOMAIN ARCHAEA Archaea are thought to be more ancient than bacteria and yet more closely related to eukaryote ancestors Archaea are extremophiles because they can live in extreme environments Ex. Boiling hot springs, salty lakes, thermal vents on the ocean floor, mud of marshes with no oxygen Very diverse nutrition requirments

15. DOMAIN EUKARYA Kingdom Protista Unicellular, colonial, or multicellular Have characteristics of plants and animals Ex. Amoebas, kelp, algae

16. DOMAIN EUKARYA Kingdom Fungi Unicellular or multicellular eukaryotes that absorb nutrients from organic materials in their environment Consist of threadlike filaments 70,000 known species

17. DOMAIN EUKARYA Kingdom Plantae More than 250,000 known species of plants All plants are multicellular Have different tissues and organs (stems, leaves, roots, etc.)

18. DOMAIN EUKARYA Kingdom Animalia More than 1,000,000 known species Heterotrophic, multicellular organisms Do not have cell walls A variety of sizes Usually arranged into very complex organs and organ systems

20. DOMAIN EUKARYA Viruses – an exception Do not posses cells and are not made up of cells Therefore, they are nonliving Not usually included in biological classification