Understanding Classification

Classification of Living Things There are 13 billion known species of organisms This is only 5% of all organisms that ever lived! New organisms are still being found and identified today.

Benefits of taxonomy Taxonomy has the benefit of classifying organisms accurately and uniformly by assigning scientifically based names It prevents misnomers such as starfish and jellyfish that aren't really fish Uses same language (Latin or some Greek) for all names

Domains Broadest, most inclusive group Three domains Archaea and Eubacteria are unicellular prokaryotes (no nucleus or membrane-bound organelles) Eukarya are more complex and have a nucleus and membrane-bound organelles

3 Domains

Kingdoms

Archaea Archaea live in harsh environments and may represent the first cells to have evolved. Ancient life forms that still survive today Found in sewage treatment plants and thermal vents Live in areas without oxygen

Eubacteria Eubacteria, only some of which cause human diseases, are present in almost all habitats on Earth. Many bacteria are important environmentally and commercially. Eubacteria are found in intestines and help break down food

Eukarya Domain The most diverse collection of organisms The largest domain of organisms Animal kingdom is the largest kingdom in this domain All eukaryotic cells (almost all .. Protista  )

Domain Eukarya Domain Eukarya is Divided into Kingdoms Protista (protozoans, algae…) Fungi (mushrooms, yeasts …) Plantae (multicellular plants) Animalia (multicellular animals)

Kingdom Protista Most are unicellular Some are multicellular Some are autotrophic, while others are heterotrophic

Kingdom Fungi Multicellular (except yeast) Heterotrophs Decomposers

Kingdom Plantae Multicellular Autotrophic Absorb sunlight to make glucose – Photosynthesis Cell walls made of cellulose

Kingdom Animalia Multicellular Heterotrophs Feed on plants and/or animals