Why Do Scientists Classify? KEY CONCEPT: Biologists use classification to organize living things into groups so that the organisms are easier to study. n Classification is grouping things together based on their similarities. n Taxonomy is the study of classification, or how living things are grouped.
The Naming System of Linnaeus KEY CONCEPT: Carolus Linnaeus devised a system of naming organisms in which each organism has a unique, 2 part scientific name. n The first part of the name is the Genus. It is always capitalized. n The second part of the name is the Species. It is always in lower case letters. n Ex. - Felis domesticus
Levels of Classification n KEY CONCEPT: The more classification levels that two organisms share, the more characteristics they have in common. n A series of 8 levels of classification are used. The largest group of the most varied organisms is the Domain. The smallest, and most specific group is a Species. Only two of the same species may mate and produce fertile offspring. n n n
Domains and Kingdoms KEY CONCEPT: Organisms are placed into Domains and Kingdoms based on their cell type, ability to make food, and the number of cells in their bodies. n n The 3 Domains are Bacteria, Archae, and Eukarya. Bacteria are Prokaryotes, have no nucleus, and are unicellular, some are autotrophs, some are heterotrophs. Archae are unicellular, are found in hot springs, are prokaryotes, and either autotrophs or heterotrophs. Bacteria and Archae differ in their chemical make-up.
Domain Eukarya KEY CONCEPT: The domain Eukarya can be further divided into 4 Kingdoms; Protista, Fungi, Plant, Animal. n All members of Eukarya have cells that contain nuclei. n Protists are unicellular. n Fungi are multicellular, heterotrophic (decomposers). Ex. - molds, yeast, fungus, mushrooms. n Plants are multicellular, autotrophic. n Animals are multicellular, heterotrophic.
5 Major Kingdoms: • • • Monera Protista Fungi Planta Animalia n n n Unicellular, prokaryotes, Bacteria Unicellular, eukaryotes & algae Multicellular, absorptive feeders, decomposers Muticellular, autotrophs Muticellular, heterotrophs
Scientific Name: n n Latin Italics or underlined Genus species Homo sapien
Family or Genus Relations? Family: n Less closely related n Larger group Genus: n More closely related n Precedes species= interbreeding Family: Felidae n Lions, tigers, leopards n house cats, cheetahs, ocelots Genus: Panthera n Leopards (pardus) n Lion (leo) n Tigers (tigris)
Feline Family Members:
Genus: Panthera (Lions &Tigers)
Classification by characteristics: n n Fossil Skulls DNA Most Useful Sequences Hair Samples Least Pictures
The Five Kingdoms