Organizational Levels

Individual organisms of the same species are organized into populations. Populations are usually found in a specific area at a specific time. Since they are members of the same species, they share the ability to mate and produce fertile offspring. Populations of different species living in the same area make up a community. All of the plants and animals living in a forest would make up a forest community.

These populations interact with each other, often in important ways. Some populations serve as food sources for other community members. Some populations, like the bacteria and fungi, breakdown dead matter so it may be recycled and reused. The community of living organisms also interacts with the non-living environment to form an ecosystem. By their very presence, living organisms can change the air, land and water of an area. In turn, the living organisms are affected by changes in the non-living environment.

Ecosystems are sometimes clustered together into large geographic units called biomes. The climate and geography of an area determine the types of plants that can live in the area. The types of plants determine what kinds of animals will be found there. Deserts and tropical rain forests are examples of two different types of biomes. There are also fresh water and salt water biomes.

The portion of our planet that can support living organisms is known as the biosphere. The biosphere extends from the atmosphere to the depths. Of the oceans. It includes the solid portion of the land where life is found. In its broadest sense, the biosphere is home to all living organisms.