objective 4: describe organisms in the six-kingdom of classification system by their...
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Objective 4: Describe organisms in the six-kingdom of classification system by their characteristics.
Recognize genus and species as components (parts) of a scientific
name.
Identify contributions of Aristotle and Linnaeus to the early history of taxonomy (science of naming &
classifying organisms).
Why learn this?
Based on Aristotle, it was once thought that there were only 2 kingdoms: plants & animals.
Over 500,000 new species have been discovered since 1978.
As DNA testing improves, a new classification system may develop.
Why Do Scientists Classify?Over 1 million organisms known & counting
Classification is the process of arranging organisms into groups based on similarities.
Biologists use classification to organize living things into groups so organisms are easier to study.
Taxonomy is the science of naming and classifying organisms.
Binomial Nomenclature: the naming system of Linnaeus
1750s Swedish naturalist Carolus Linnaeus devised a system of naming organisms that is still used today.
Based it on his observations & gave each organism a 2-part name, thus, binomial, meaning “two parts”
Binomial Nomenclature
Scientists around the world use this system to identify all living organisms.
It assigns the Latin words Genus (capitalized) and species (lowercased) name as the scientific name. Both are written in Italics.
Example: Homo sapiens
Comprehension Check?
What is binomial nomenclature?
What is a scientific name?
What is taxonomy?
Why classify anything?
Levels of Classification
Today’s system is based on Linnaeus’s contributions but is much more advanced with many more levels.
Example: How would I find out how many students live on the continent of North America, in the United States, in Alabama, in Mobile County, in Mobile, in my neighborhood, on my street, and attend my school?
There are 8 levels currently:Domain, Kingdom, Phyla (Phylum), Classes, Orders, Families, Genera (Genus), and Species
Pneumonic for remembering the levels of classification:
D: _____________ Dominant (Domain)
K: _____________ Kings (Kingdom)
P: _____________ Play (Phyla)
C: _____________ Chess (Class)
O: _____________ On (Order)
F: _____________ Fine (Family)
G: _____________ Grained (Genus)
S: _____________ Sand (Species)
Levels of Classification
Organisms are put into a broad group and then each group is further divided as it becomes more specific.
The more levels of classification that 2 organisms share the more characteristics they have in common.
Example of classification levels
Domain: EukaryaKingdom: Animalia
Phylum: Chordata– Class: Mammalia
» Order: Primates» Family: Hominidae» Genus: Homo» Species: sapiens
Domains and Kingdoms
3 Domains with kingdoms within themOrganisms are put into domains & kingdoms based on 3 things:
Cell type: prokaryotes or eukaryotes
Ability to make food: heterotroph or autotroph
Number of cells in bodies: unicellular (1 cell) or multicellular (many cells)
3 Domains
Bacteria: prokaryotes (no nucleus), autotrophic or heterotrophic, microscopic
Archaea (Archeabacteria): prokaryotes (no nucleus), autotrophic or heterotrophic; microscopic; no cell walls; extreme environments (hot, cold, salty, acidic)
Eurkarya: eukaryotes, nucleus; in 4 kingdoms—protists, fungi, plants, or animals
Domain: Eurkarya, Kingdom: Protista (the protists)
CANNOT be classified as plant, animal, or fungus
“odds and ends” kingdom
Mainly unicellular others multicellular, so it is usually referred to as single-celled/unicellular
Classified by the way they get energy--some autotrophs others heterotrophs
Examples of Protists
Euglena: use flagella to move
Amoeba:Use pseudopods(false feet; cytoplasmicExtensions to move)
Protist-like plants: Algae, the solution to fuel crisis
Algae produce biodiesel.http://www.greenstrides.com/2008/04/01/algae-could-prove-to-be-the-best-biofuel/
Algae and the fuel crisis: large scale algae farm/wastewater treatment facility
http://inhabitat.com/researchers-use-algae-to-treat-wastewater-and-generate-biofuel/
Domain Eukarya, Kingdom Fungi
Multicellular eukaryotes except yeasts which are unicellullar
Heterotrophs, can act as decomposers
Absorb nutrients to get energy
Cell walls present
Reproduce using spores
Examples: molds, yeasts, mushrooms
Domain: Eurkarya, Kingdom: Plantae
Eukaryotic, multicellular w/cell walls & choloroplasts (photosynthesis)
Autotrophic—they are producers
Cell wall made from cellulose—the crunchy stuff you taste in celery & lettuce
Fixed in place, don’t move—they are sessile
Domain: Eukarya,Kingdom: Animalia
Multicellular
Advanced nervous system that allows them to respond to environment
Reproduce sexually or asexually
Highly mobile
Heterotrophic—they are consumers
Interdependent on other organisms