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CLASSIFICATION OF LIVING THINGS
WHY DO WE CLASSIFY THINGS? Supermarket Aisles Libraries Classes Teams/sports Members of a family Roads Cities Money
WHAT IS CLASSIFICATION? **Classification: putting things into orderly groups based on similar characteristics **Taxonomy: the science of describing, naming, and classifying organisms
EARLY CLASSIFICATION Aristotle grouped everything into simple groups such as animals or plants He then grouped animals according to if they had blood or didn’t have blood, and if they had live young or laid eggs, and so on…
EARLY CLASSIFICATION n n n Organism’s were grouped into land dwellers, water dwellers, and air dwellers. Plants were placed into three categories based on the differences in their stems. As new organism’s were discovered, his system became inadequate. n Categories were not specific enough. n Common names did not describe a species accurately. n Names were long and hard to remember.
**BINOMIAL NOMENCLATURE: A SYSTEM CALLED BINOMIAL NOMENCLATURE USED FOR NAMING LIVING THINGS AND GROUPING SIMILAR ORGANISMS INTO CATEGORIES. **Developed by Carolus Linnaeus Swedish Biologist 1700’s **Two-name system **Genus and species named using Latin or Greek words
**RULES USED TO WRITE SCIENTIFIC NAMES Homo sapiens An organism’s genus is always written first; the organism’s species is always written second The genus is Capitalized; the species is written in lower case Scientific names of organisms are always italicized or underlined
**THE MODERN SYSTEM OF CLASSIFICATION HAS 8 LEVELS: Domain Kingdom Phylum Class Order Family Genus Species
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 copyright cmassengale 11
TERMINOLOGY Getting food autotrophs – make own food hetertrophs – get food from other sources Type of cells prokaryotic – no nucleus, membrane bound organelles, DNA is circular (plasmid), do contain ribosomes, smaller eukaryotic – with a nucleus and organelles, DNA in chromosomes, larger
TERMINOLOGY CONTINUED Body type unicellular – made of only one cell multicellular – made of more than one cell; -have cells with special functions Reproduction sexual – need male and female parents asexual – need only one parent
HELPFUL WAY TO REMEMBER THE 8 LEVELS **Dumb kids playing catch on freeways get squashed
Levels of Classification • Remember: King Philip Came Over For Grandma’s Soup. Kingdom Phylum Class Order Family Genus Species
Classification Hierarchy of Organisms
n Modern System: n n n Each kingdom (plant and animal) was divided into a phylum* (division for plants) Each phylum into a smaller groups called class. Each class was divided into an order. Each order was divided into family (families). Each family was divided into a genus (pluralgenera) Each genus was divided into a species. (scientific name) *Note: Phyla and family were not in Linnaeus’s classification system but were added by modern scientists.
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
Bacteria Domain: There are typically 40 million bacterial cells in a gram of soil and a million bacterial cells in a milliliter of fresh water. Bacteria were among the first life forms to appear on Earth, and are present in most of its habitats. Bacteria inhabit soil, water, and the deep portions of Earth's crust. Bacteria also live in symbiotic and parasitic relationships with plants and animals.
These microbes (archaea; singular archaeon) are prokaryotes, meaning that they have no cell nucleus or any other membranebound organelles in their cells. They have since been found in a broad range of habitats, including soils, oceans, and marshlands. They are also found in the human colon, oral cavity, and skin.  Archaea are particularly numerous in the oceans, and the archaea in plankton may be one of the most abundant groups of organisms on the planet.
Domain Eukarya – eukaryotes, organisms that contain a membrane-bound nucleus. There is an inexhaustive list of eukaryotic organisms.
THE SIX KINGDOMS REVIEW Eubacteria- “true” bacteria (prokaryotic) Archaebacteria – “ancient” bacteria (prokaryotic” Protista – WEIRD organisms!!!! (eukaryotic) Fungi – digest dead or decaying matter (eukaryotic) Plantae - stationary, photosynthetic (eukaryotic) Animalia – mobile heterotrophs (eukaryotic)
Most bacteria are in the EUBACTERIA kingdom. . Eubacteria are classified in their own kingdom because their chemical makeup is different. Most eubacteria are helpful.
Some produce vitamins and foods like yogurt. However, these eubacteria, Streptococci pictured above, can give you strep throat!
Archaebacteria have unique protein-like cell walls and cell membrane chemistry, and distinctive ribosomes.
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PROTISTA • Most are unicellular • Some are multicellular • Some are autotrophic, while others are heterotrophic • Aquatic copyright cmassengale 41
FUNGI • Multicellular, except yeast • Absorptive heterotrophs (digest food outside their body & then absorb it) • Cell walls made of chitin 42
PLANTAE • Multicellular • Autotrophic • Absorb sunlight to make glucose – Photosynthesis • Cell walls made of cellulose 43
ANIMALIA • Multicellular • Ingestive heterotrophs (consume food & digest it inside their bodies) • Feed on plants or animals copyright cmassengale 44
HUMANS Humans are named: Homo sapiens Homo because of our large brain and upright posture. sapiens because of our intelligence and ability to speak.
CLASSIFICATION TOOLS A dichotomous key is a series of descriptions arranged in pairs that lead the user to the identification of an unknown organism.
"Dichotomous" means “divided into two parts” Greek origin
1. a. wings covered by an exoskeleton – go to step 2 b. wings freely observed – Go to step 3 2. a. body has a round shape ………. ladybug, a red beetle with black spots b. body has an elongated shape ………. grasshopper, a green insect that hops 3. a. wings point out from the side of the body ………. dragonfly, an insect that is 10 - 15 cm long and lives in marshes b. wings point to the posterior of the body ………. housefly, a flying insect with red eyes and an annoying buzz
Dichotomous key Another Example of a dichotomous key…
1. Divides a larger group in smaller groups 2. Typically, it may separate objects into groups that “have it” and those that “don’t have it”
Carefully observe objects to “notice” similarities and differences Place objects into either one group or another – not both groups Examine each group you create – to see if it can be further subdivided
TAXONOMIC KEY 1 a Fruits occur singly. . . Go to 3 1 b Fruits occur in clusters of two or more. . . . Go to 2 2 a Fruits are round. . . . Grapes 2 b Fruits are elongate. . . Bananas 3 a Thick skin that separates easily from flesh. . Oranges 3 b Thin skin that adheres to flesh. . . . Go to 4 4 a More than one seed per fruit. . . . Apples 4 b One seed per fruit. . . Go to 5 5 a Skin covered with fuzz. . . . . Peaches 5 b Skin smooth, without fuzz. . . . Plums What steps would you use to identify an apple?
DICHOTOMOUS KEY OF ANIMALS Animals with 4 legs
Dichotomous Key of Animals with 4 legs: Horse, gorilla, cow Ostrich, worm, shark, man, rooster
Dichotomous Key of Animals with 4 legs : Horse, gorilla, cow Animals with tail: Ostrich, worm, shark, man, rooster
Dichotomous Key of Animals with 4 legs: Horse, gorilla, cow Ostrich, worm, shark, man, rooster Animals with a tail: Horse, cow gorilla Animals with utters: cow horse
IDENTIFICATION OF INSECTS ONLINE DICHOTOMOUS KEY ACTIVITY http: //www. insectidentification. org/arachnid-key. asp
Dichotomous Key on Norns belong to the genus Norno and can be divided into eight species that are generally located in specific regions of the world. Use the dichotomos key to identify the norns below. Write their complete scientific name (genus + species) in the blank. 1. Has pointed ears. . . . go to 3 . . Has rounded ears. . . . go to 2 2. Has no tail. . . . . Kentuckyus . . Has tail. . . . . Dakotus 3. Ears point upward. . . . go to 5 . . Ears point downward. . . go to 4 4. Engages in waving behavior. . . . Dallus . . Has hairy tufts on ears. . . . Californius 5. Engages in waving behavior. . . . . Wala . . Does not engage in waving behavior. . . . go to 6 6. Has hair on head. . . . . Beverlus . . Has no hair on head (may have ear tufts). . . . go to 7 7. Has a tail. . . . Yorkio . . Has no tail, aggressive. . . . Rajus
EXIT TICKET On a half sheet of paper: List the 6 kingdoms we talked about today