Objective 4: Describe organisms in the six-kingdom of classification system by their characteristics. Recognize genus and species as components (parts) of a scientific name. Identify contributions of Aristotle and Linnaeus to the early history of taxonomy (science of naming & classifying organisms). Why learn this? Based on Aristotle, it was once thought that there were only 2 kingdoms: plants & animals. Over 500,000 new species have been discovered since 1978. As DNA testing improves, a new classification system may develop. Why Do Scientists Classify? Over 1 million organisms known & counting Classification is the process of arranging organisms into groups based on similarities. Biologists use classification to organize living things into groups so organisms are easier to study. Taxonomy is the science of naming and classifying organisms. Binomial Nomenclature: the naming system of Linnaeus 1750s Swedish naturalist Carolus Linnaeus devised a system of naming organisms that is still used today. Based it on his observations & gave each organism a 2-part name, thus, binomial, meaning “two parts” Binomial Nomenclature Scientists around the world use this system to identify all living organisms. It assigns the Latin words Genus (capitalized) and species (lowercased) name as the scientific name. Both are written in Italics. Example: Homo sapiens Comprehension Check? What is binomial nomenclature? What is a scientific name? What is taxonomy? Why classify anything? Levels of Classification Today’s system is based on Linnaeus’s contributions but is much more advanced with many more levels. Example: How would I find out how many students live on the continent of North America, in the United States, in Alabama, in Mobile County, in Mobile, in my neighborhood, on my street, and attend my school? There are 8 levels currently: Domain, Kingdom, Phyla (Phylum), Classes, Orders, Families, Genera (Genus), and Species Pneumonic for remembering the levels of classification: D: _____________ K: _____________ P: _____________ C: _____________ O: _____________ F: _____________ G: _____________ S: _____________ Dominant (Domain) Kings (Kingdom) Play (Phyla) Chess (Class) On (Order) Fine (Family) Grained (Genus) Sand (Species) Levels of Classification Organisms are put into a broad group and then each group is further divided as it becomes more specific. The more levels of classification that 2 organisms share the more characteristics they have in common. Example of classification levels Domain: Eukarya Kingdom: Animalia Phylum: Chordata – Class: Mammalia » Order: Primates » Family: Hominidae » Genus: Homo » Species: sapiens Domains and Kingdoms 3 Domains with kingdoms within them Organisms are put into domains & kingdoms based on 3 things: Cell type: prokaryotes or eukaryotes Ability to make food: heterotroph or autotroph Number of cells in bodies: unicellular (1 cell) or multicellular (many cells) 3 Domains Bacteria: prokaryotes (no nucleus), autotrophic or heterotrophic, microscopic Archaea (Archeabacteria): prokaryotes (no nucleus), autotrophic or heterotrophic; microscopic; no cell walls; extreme environments (hot, cold, salty, acidic) Eurkarya: eukaryotes, nucleus; in 4 kingdoms—protists, fungi, plants, or animals Domain: Eurkarya, Kingdom: Protista (the protists) CANNOT be classified as plant, animal, or fungus “odds and ends” kingdom Mainly unicellular others multicellular, so it is usually referred to as singlecelled/unicellular Classified by the way they get energy-some autotrophs others heterotrophs Examples of Protists Euglena: use flagella to move Amoeba: Use pseudopods (false feet; cytoplasmic Extensions to move) Examples of Protists Paramecium Use cilia to move Seaweed: float Plant-like protists: diatoms Plant like protists: algae Protist-like plants: Algae, the solution to fuel crisis Algae produce biodiesel. http://www.greenstrides.com/2008/04/01/algae-could-prove-to-be-the-bestbiofuel/ Algae and the fuel crisis: large scale algae farm/wastewater treatment facility http://inhabitat.com/researchers-use-algae-to-treat-wastewater-andgenerate-biofuel/ Plant like protists: Dinoflagellates The culprits behind toxic red tide events. Fungus like protists: slime mold Domain Eukarya, Kingdom Fungi Multicellular eukaryotes except yeasts which are unicellullar Heterotrophs, can act as decomposers Absorb nutrients to get energy Cell walls present Reproduce using spores Examples: molds, yeasts, mushrooms Fungi Examples Yeast (Candida albicans) Fungi Examples Bread mold, Rhizopus, the happy accident of penicillin Examples of Fungal Spores Mushroom spores Toxic molds: Stachybotrys chartarum or Stachybotrys atra Domain: Eurkarya, Kingdom: Plantae Eukaryotic, multicellular w/cell walls & choloroplasts (photosynthesis) Autotrophic—they are producers Cell wall made from cellulose—the crunchy stuff you taste in celery & lettuce Fixed in place, don’t move—they are sessile Example of plant: “angel trumpets” Domain: Eukarya,Kingdom: Animalia Multicellular Advanced nervous system that allows them to respond to environment Reproduce sexually or asexually Highly mobile Heterotrophic—they are consumers Interdependent on other organisms Example of animal: Zdonk Zdonk Cross b/w Donkey & zebra