Biological Classification Why is it important We use

Biological Classification Why is it important? • We use classification in biology to organize the diversity of life – to illustrate the relationships among living things – to identify specific species – to provide scientific names to organisms • Without classification, it would be difficult to study life – think of the disorganized pile of clothes!

Biological Classification: Taxonomic Hierarchy

By the end of class, you will be able to… • Explain the importance of a scientific naming system • Evaluate organisms’ relatedness based on their taxonomic hierarchy • List the 7 levels in the taxonomic hierarchy • Give a brief overview of each of the six kingdoms

Modern Classification • Every year, thousands of new species are discovered. • Biologists classify newly discovered organisms with organisms having similar characteristics. • The way we group organisms continues to change • Today these methods reflect the evolutionary history of organisms.

Who started it? • • • Carolus Linneus Botanist Mid-1700 s Uses Latin names Created a hierarchy – Hierarchy = “tiered” or “layered” – 7 levels – 3 primary divisions: animal, plant, and mineral

Today, we have 8 levels of classification. Linneus – 7 levels Not from Linneus. Most general; many organisms Spinal cord Species: A group of organisms capable of interbreeding, who interbreed in their natural environment, and who produce fertile offspring. Mammary glands, fur, placenta Canine teeth Felines Large cats Most specific ; 1

Kingdom Animalia Phylum Chordata Mammalia Class Order Carnivora Urisdae Family Genus Species Ursus arctos

Where does that name come from? • • Binomial nomenclature Developed by Linneus Latin Most specific way to name an organism Format: Genus species Genus is capitalized, species is lower case Name should be underlined or written in italics

Why use scientific names? • Universal – used everywhere • Common names can be confusing – Consider the pineapple. Is it a pine? Is it an apple? – Which is more poisonous: the water moccasin or the cottonmouth? – Raise your hand when you know what the following organism is:

Raise your hand when you know… • Isopod • Sow Bug • Pill Bug • Roly Poly Bug • Scientific Name: Armadilidium vulgare

Let’s bring it all together… • So, why is biological classification important? • What are the 7 levels of the taxonomic hierarchy? • Which are more closely related: organisms from the same genus or organisms from the same family? Why? • Why do we use scientific names?

Which are more closely related on the taxonomic hierarchy: a mushroom and a squirrel -ORa mushroom and a daisy? Why?

Intro to Kingdoms

Classification of Living Things DOMAIN Bacteria Archaea KINGDOM Eubacteria Archaebacteria CELL TYPE CELL STRUCTURES Eukarya Protista Fungi Prokaryote Cell walls with peptidoglycan Cell walls of Cell walls without Cell walls of cellulose in some; chitin peptidoglycan some have chloroplasts Unicellular NUMBER OF CELLS Unicellular MODE OF NUTRITION Autotroph or heterotroph EXAMPLES Streptococcus, Escherichia coli Autotroph or heterotroph Methanogens, halophiles Eukaryote Plantae Animalia Eukaryote Cell walls of cellulose; chloroplasts No cell walls or chloroplasts Most unicellular; Multicellular some colonial; Most some multicellular; some unicellular Autotroph or Heterotroph heterotroph Autotroph Amoeba, Paramecium, Mushrooms, slime molds, giant yeasts Mosses, ferns, kelp flowering plants Multicellular Heterotroph Sponges, worms, insects, fishes, mammals

Archaebacteria • Often live in extreme environments • Prokaryotic – Lack a distinct nucleus with nuclear membrane • Unicellular • Cell walls – Do not contain peptidoglycan • Can be autotrophs or heterotrophs

Eubacteria • Prokaryotic • Unicellular • Cell wall – Made of peptidoglycan • Can be autotrophs or heterotrophs • Evolved SEPARATELY from archaebacteria!

Protista • Eukaryotic – Membrane bound nucleus • May be unicellular or multicellular • Can be autotrophs or heterotrophs • May have chloroplasts • Cell wall may be present – Made of cellulose

Fungi • Eukaryotic – Nucleus surrounded by nuclear membrane • Most multicellular, some unicellular • Heterotrophic • No chloroplasts • Cell Wall – Made of chitin

Plantae • Eukaryotic – Nucleus with nuclear membrane • Multicellular • Cell Wall – Made of cellulose • Autotroph – Contain chloroplasts

Animalia • Eukaryotic – Nucleus with nuclear membrane • • Multicellular No cell wall No chloroplasts Heterotroph