Classification of Living Things Scientists estimate that there are between 3 million and 100 million species of organisms on Earth. Taxonomy—The grouping of organisms based on similarities in structure. Taxonomists--biologists who specialize in identifying and classifying life on our planet--have named approximately 1.7 million species so far. Each year, about 13,000 new species are added to the list of known organisms. So, how do scientists classify (organize) all these millions of species?

Classification of Living Things Carolus Linaeus (1707-1778) Grouped organisms based on similarities in structure (taxonomy) Divided all living things into animal or plant Subdivided organisms based on degree of relatedness by structure and appearance Scientific discoveries have led to other methods of classification Using embryonic structures, evolutionary origins, and biochemical similarities

Classification of Living Things The current system uses 3 overarching Domains and 6 Kingdoms Domains Archaea Bacteria Eukaryota Kingdoms Archaebacteria Eubacteria Protista Fungi Plantae Animalia

Scientific Name: used to avoid confusion based on Latin or Greek Genus name (capitalized)  species name (lower case) Blue Whale Balaenoptera musculus Kingdom: Animalia Phylum: Chordata Class: Mammalia (Unranked) Cetacea (Unranked) Mysticeti Family: Balaenopteridae Genus: Balaenoptera Species: B. musculus

Life's History and Diversity 4/26/2017 2 Types of Cells PROKARYOTES EUKARYOTES organisms with no nuclear membrane organisms with a nuclear membrane The Big Picture 3 Domains 6 Kingdoms Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 3 Domains and 6 Kingdoms Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 Domain: Archae Kingdom archaebacteria Best known for living in extremely hostile environments (very hot, very acidic, or very salty), but they can also be found in less extreme conditions. Unicellular Volcanic Hot Springs Believed to be the earliest form of life on Earth. Although both archaea and bacteria are simple life-forms, archaea are very different from bacteria. Hydrothermal Vents Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 Domain: Bacteria Kingdom Eubacteria Considered “true bactera” Over 5000 species of bacteria Magnetic bacteria in saltwater marshes cling to iron deposits in sediment Chemoautotrophic bacteria use hydrogen sulfide to make food (hydrothermal vents) Bacteria (Staphylococcus aureus; yellow spheres) adhering to nasal cilia. Mycoplasma hyopneumoniae Borrelia burgdorferi, the bacterium that causes Lyme disease. E. Coli bacteria There are more bacteria in your mouth than there have been people living since the dawn of humans. Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 Bacteria Microscopic, single-celled organsms Have a thick outer wall surrounding the cell membrane Prokaryotic (no nucleus) Some are aerobic (require oxygen) Some are anaerobic (no oxygen) Classified and named based on 3 basic shapes Coccus – round Bacillus – rod shaped Spirillum – spiral shaped Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 Decay Bacteria Bacteria that break down organic matter, releasing molecules into water, recycling and making nutrients avaiable (ex. phoshpate, nitrate, sulfate) Called “decomposers” Most common in bottom sediments Also found in warm, moist, dark environments rich in food Biol 1010, G. Podgorski

Life's History and Diversity 4/26/2017 Blue Green Bacteria Resemble algae, contain chlorophyll Resembles bacteria (lacks membrane bound nucleus) Called “cyanobacteria” – blue or green in color, some also have red pigments Found throughout the oceans Survive in a variety of conditions Can survive in water or sediment low in oxygen First photosynthetic organisms on earth! Form stromatolite fossils more than 3 billion years old! Biol 1010, G. Podgorski

The Domain Eukarya is divided into 4 Kingdoms: Protista Fungi Plantae Animalia

PROTISTS • Protists are eukaryotes because they all have a nucleus. • Earliest was about 1.5 billion years ago • Protozoans (ameoba, paramecium) and algae • Many are unicellular and all groups (with one exception) contain some unicellular members. A better name for Protists would be "Eukaryotes that are neither Animals, Fungi, nor Plants". Protists

FUNGI Eukaryotic, unicellular, and multicellular Fungi sometimes look like plants, but they’re not! Eukaryotic, unicellular, and multicellular Unable to make own food Absorb nutrients from dead and decaying material Examples: Mushrooms and yeast

Plantae Animalia Eukaryotic, multicellular Have chlorophyll for photosynthesis Use water and carbon dioxide to make food Have cell wall Eukaryotic, multicellular Heterotrophic Many capable of movement No cell wall Classified further into invertebrates and vertebrates

Kingdom Phylum Class Order Family Genus Species Remember: King Philip Came Over For Good Spaghetti