Classification

Categories of Biological Classification: 

Categories of Biological Classification Binomial Nomenclature

Objectives: 

Objectives Describe Linnaeus’s role in developing the modern system of naming organims . Summarize the scientific system for naming species. List the seven levels of biological classification

Taxonomy: 

Taxonomy Classifications makes the discussion of different types of organisms possible. Just as postal workers use first zip code, and then address, and then name to deliver mail to its intended recipient, biologists use a system of hierarchy to place organisms into categories. Aristotle was the first naturalist to group organisms according to structural similarities. Romans and Greeks later grouped organisms according to basic categories such as “oak trees” or “dogs” or “horses”. Eventually, each category of classification became known as a genus. The science of naming and classifying organisms is called taxonomy.

A Simpler System: 

A Simpler System The Swedish Biologist Carl Linnaeus developed an easier method for classifying organisms. Linnaeus’ system provides for a two-name or binomial nomenclature for each organism. His system uses a genus name followed by a species. For example, the European Honey Bee is called Apis millifera . The first or genus name is always capitalized and the second or species name never is. In the 250 years since Linnaeus invented the system, it has been universally adopted. Most of the species he name in 1753 still carry the same designations.

Scientific Names: 

Scientific Names Genus: A taxonomic category containing similar species. Organisms of the same genus share important characteristics. Species: The basic biological unit. Members of the same species are capable of breeding and producing viable offspring. Example: The genus Quercus is composed of Oak trees. The specific species Quercus rubra is the Red Oak tree.

Common Ground: 

Common Ground The reason we use this system of naming is to give scientists a common ground when discussing organisms. Example: In the United States, the distinction Turdus migratorius is given to Robins, a large song bird with a red breast, common in the US. In the United Kingdom, what are considered Robins are actually Erithacus rubicula . If scientists from both areas meet to discuss birds and only used common names they would never know they were talking about to completely different species. All scientific names are unique

Classification Groups: 

Classification Groups Linnaeus worked out a broad system of classification for all animals and plants based or form and structure. The system is divided into 8 levels. D o K indly P ay C ash O r F urnish G ood S ecurity is a tool we use to remember D omain, K ingdom, P hyla, C lass, O rder, F amily, G enus, and S pecies. There are three domains, Bacteria and Archaea both contain prokaryotic bacteria while the domain Eukararya contains all Eukaryotes.

Classification Example: 

Classification Example The European honey bee would be fully classified as follows: Domain: Eukarya Kingdom: Anamilia Phylum: Arthropoda Class: Insecta Order: Hymenoptera Family: Apidae Genus: Apis Species: melifera Every organism on Earth fits into a category like this.

What Does it Mean: 

What Does it Mean Each level of the classification tells you something about the organism. The domain tells us that the cells of the organism have a nucleus. The Kingdom tells us that the organism is a multicellular heterotroph . The phylum tells us that the organism has an exoskeleton, a segmented body, and jointed limbs. The class tells us that the organism has 6 limbs and a three segmented body.

Homework: 

Homework P 304, questions 1-4 P 300, define key terms Due Tuesday at the beginning of class.