Classification Sorting it all out
Why Classify? Classification is putting things into orderly groups based on similar characteristics. Allows us to figure how many species there are in the world Tells us the defining characteristics of each species Shows us the relationship between species Think of a classification system you may use in your everyday life. Why do you use this system?
Taxonomy Taxonomy: the science of describing, naming, and classifying organisms In the 1700’s Carolus Linnaeus discovered the seven level system of classification that we still use today These levels of classification incorporate all of the living organisms of the world. Even though we are constantly discovering new organisms and new species, we are able to fit these new species into Linnaeus’ levels of classification.
Seven Levels of Classification Domain Kingdom Phylum Class Order Family Genus Species
Domains A three-domain system is used to classify living organisms. Organisms are placed into domains and kingdoms based on their cell type, their ability to make food, and the number of cells in their body. 1.Bacteria (Eubacteria): unicellular prokaryotes (cells lack a nuclueus), Some are autotrophs while others are heterotrophs Some are harmful (ex. Strep throat) and some helpful (ex. yogurt) Very common Kingdom of Eubacteria
Domains cont… 2. Archaea: unicellular prokaryotes Archaea is Greek for “ancient”, these organisms are the oldest known organisms on Earth Some are autotrophs while others are heterotrophs Can be found in deep ocean with hot gasses and molten rock, salty water, swamps, and even intestines of a cow! These harsh living conditions are related back to the ancient world Different chemical make-up than bacteria Not as common as bacteria Kingdom of Archaeabacteria
Domains cont… 3. Eukara: eukaryotes (cells contain nuclei) Organisms in this domain can be classified into 4 kingdoms Protists Fungi Plants Animals
Kingdoms Largest level of classification Archaebacteria Eubacteria Contains similar phyla There are 6 different kingdoms Archaebacteria Eubacteria Protista Fungi Plantae Animalia
Kingdom History
Levels of classification Animal Kingdom Phylum Chordata Class Mammalia Order Carnivora Family Felidae Genus Felis Species Felis domesticus All animals are in the kingdom Animalia. All animals in the phyllum Chordata have a hollow nerve cord. Most have a backbone. Animals in the class Mammalia have a backbone. They also nurse their young. Animals in the order Carnivora have a backbone, nurse their young, and have special teeth for tearing meat. Animals in the family Felidae are cats. They have a backbone, nurse their young, have special teeth for tearing meat, and have retractable claws. Animals in the genus Felis have traits of other animals in the same family. However, these cats cannot roar- they can only purr. The species Felis domesticus is the common house cat. The house cat shares traits with all of the organisms in the levels above the species level, but also has unique traits.
Which kingdom? Organisms are divided into kingdoms based on…. Cell Type – Prokaryote (no nuclei) or Eukaryote (nuclei)
Which Kingdom cont… 2. Cell Number- unicellular or multicellular 3. Feeding Type- autotroph or heterotroph
Key Characteristics of Domains & Kingdoms Cell Type Cell # Feeding Type Cell Wall Fact or Example Archaebacteria Eubacteria Protista Fungi Plantae Animalia Bacteria Fungi
Archaebacteria Ancient bacteria Live in harsh/extreme environments Prokaryote Unicellular Autotrophs and heterotrophs Cell wall is present- contains no peptidoglycan (polymer)
Eubacteria.. Or just plain bacteria When people talk about bacteria, this is the type they usually mean Live in more neutral conditions Prokaryote Unicellular Some autotrophs and some heterotrophs Cell Wall present Nitrifying bacteria (autotroph) E.Coli, helps break down food in your intestines (heterotroph)
Protists All eukaryotes that are not plants, animal, or fungi Unicellular and simple multicellular organisms There are animal-like protists called protozoans (no cell wall), that are heterotrophs There are plant-like protists like algae (cell wall present), that are autotrophs Slime molds, water molds Odds and ends group
Fungi Molds and mushrooms Unlike plants, fungi Do NOT perform photosynthesis Unlike animals, fungi do NOT eat food Heterotrophs, absorb nutrients from substances in their suroundings Reproduce using spores Eukaryotic cells Multicellular Cell wall present
Plants Eukaryotic cells, multicellular Cell wall present Create own food through photosynthesis, making plants autotrophs Plants provide nutrients and habitat for other organisms
Animals Complex, multicellular organisms Eukaryotic No cell wall present Usually able to move around, and have specialized sense organs Usually have quick response to environment Animals depend on plants and other animals for food, making animals heterotrophs Animals depend on bacteria/fungi to recycle nutrients found in dead organisms Simple organisms like worms, insects, corals, and sponges are also animals
Phylum Examples in Animal Kingdom Chordata- dorsal nervous chord (spinal column) Mollusca- muscular foot, shell Cnidaria- Have cnidae (stinging cells), have a nerve net but no true nervous system, no head, 2 way gut Annelida- segmented, bilaterally symmetrical, closed circulatory system, setae There are 35 different phyla in the Animal Kingdom alone!
Classification of Man Kingdom Animalia Phylum Chordata Class Mammalia Order Primates Family Hominidae Genus Homo Species sapien
Binomial Nomenclature aka Scientific Name Binomial = TWO terms Nomenclature = given NAME Linnaeus discovered a scientifically useful way to name organisms no matter how many common names there may be Ex.) In North and South American, a certain large cat is called a mountain lion by some people, a cougar by others, and a puma still by others. However, its scientific name is always the same, Felis concolor Genus + species = scientific name Scientific names are written in italics, the Genus always capitalized and the species lowercase.
Is your table filled out?