A species is a group of organisms, similar to one another; they can breed and produce fertile offspring.
Population or group of individuals belongs to the same species, which live in the same area.
Communities, or assemblages of different population, live together in a defined area.
An ecosystem is a collection of organisms that live in a particular place, together with their non-living, or physical environment.
A biome is a group of ecosystems that have the same climate and similar dominant communities.
Biosphere is the highest level of organization; it is the global sum of all the ecosystems.