5.5 Classification

Binomial System of Nomenclature

• System of classifying organisms based on two (“bi”), names (“nomial”), which are organized in a system (“nomenclature”)

• Ex: we are Homo sapiens– First word capitalized (refers to the genus)– Second word not capitalized (refers to the species)– Both words italicized when typed or underlined when

handwritten – Typically words are Latin or Greek

• This binomial nomenclature system for naming and organizing species was popularized by Carolus (Carl) Linnaeus

• Why should we organize organisms like this?– Helps make sense of the biosphere– Helps show evolutionary links– Helps predict characteristics shared

by many members of a group– Keeps consistency between

scientists of various areas, languages, cultures

The Seven Taxa• The correct order for classifying organisms is

Kingdom, Phylum, Class, Order, Family, Genus, Species

– Create a mnemonic device and write it in your notes so you can correctly remember the order

Taxa Human

Kingdom Animalia

Phylum Chordata

Class Mammalia

Order Primate

Family Hominidae

Genus Homo

Species sapiens

Dichotomous Key

• A key or flowchart that is used by answering questions as yes or no in order to determine which order, genus, or species an organism belongs to

Dichotomous Key –Family: Candae1a. Candy contains chocolate … 21b. Candy contains no chocolate … 52a. Candy contains nuts … 32b. Candy contains no nuts … 63a. Candy is square … Snickers3b. Candy is rounded/circular … 44a. Candy contains pureed/smooth nuts … Reese Cup4b. Candy contains large pieces of nuts … Almond Joy5a. Candy is individually wrapped … Starburst5b. Candy is not individually wrapped … Skittles6a. Candy comes as bite-size pieces … M&M’s6b. Candy comes as a whole bar … 77a. Candy contains caramel … Milky Way7b. Candy contains fluffy nougat … 3 Musketeers

Homework:Our next assignment will be whiteboarding different

plant and animal classifications and then sharing with the class. Your homework will be to take an

organism within one of the classifications and create a dichotomous key for that organism. Your

key must contain no fewer than 8 organisms. Dichotomous key due next class.

Whiteboarding Assignment• With your assigned partner, whiteboard some

simple external recognition features so that we can distinguish between the 10 different phyla.

Bryophyta Filicinophyta Coniferophyta Angiospermophyta

Porifera Cnidaria Platyhelminthes Annelida

Mollusca Arthropoda