Organisms and components of organisms are seperated into levels of organization so that they can be referenced. For example, a group of squirrels living in an area together can be called a population of squirrels. Likewise, all of the organisms that interact with one another in and around a lake can be called a biological community.
Biosphere
all ecosystems on earth
Ecosystem
a biological community and all of its non-living surroundings
Example: All of the organisms in Eastern South Dakota as well as the non-living things surrounding them like shade, air temperature, and rainfall.
Community
populations of organisms that coexist in an area
Example: All of the organisms in Eastern South Dakota.
Population
group of one type of organism living in an area together
Example: All of the pheasants living in Eastern South Dakota.
Organism
individual living thing
Example: One pheasant.
Organ System
groups of cells that share a specialized function
Example: The circulatory system of a pheasant.
Cells
smallest functional unit of life
