Niche
The Role And Position Of An Organism Within Its Ecosystem, Including How It Obtains Resources And Interacts With Other Species.

Habitat
The Natural Environment In Which An Organism Lives, Including Physical Factors Such As Climate And Soil And Biological Factors Such As Other Species.

Species
A Group Of Organisms That Can Interbreed And Produce Fertile Offspring And Are Reproductively Isolated From Other Such Groups In Nature.

Biosphere
The Global Sum Of All Ecosystems On Earth, Including All Living Organisms And The Environments In Which They Live.

Ecosystem
A System Consisting Of A Community Of Living Organisms And The Nonliving Components Of Their Environment Such As Air, Water, And Soil.

Community
All The Different Populations Of Organisms That Live And Interact In The Same Area.

Population
A Group Of Individuals Of The Same Species Living In A Particular Area And Capable Of Interbreeding.

Organism
An Individual Living Thing Such As A Bacterium, Plant, Or Animal That Can Carry Out All Basic Life Processes Within Its Cells And Organ Systems.

Organ System
A Group Of Organs That Work Together To Carry Out Major Functions Such As Digestion, Circulation, Or Respiration In A Multicellular Organism.

Organ
A Structure Composed Of Different Types Of Tissues That Work Together To Perform A Particular Function In An Organism.