The Biosphere

• The part of Earth that supports life is the biosphere (BI uh sfihr).

The biosphere includes the top portion of Earth’s crust, all the waters that cover Earth’s surface, and the atmosphere that surrounds Earth

The Biosphere

The biosphere is made up of different environments that are home to different kinds of organisms.

For example, desert environments receive little rain

Cactus plants, coyotes, and lizards are included in the life of the desert

Ecosystems

An ecosystem consists of all the organisms living in an area, as well as the nonliving parts of that environment

Populations

• A population is made up of all organisms of the same species that live in an area at the same time.

For example, all the bison in a prairie ecosystem are one population

Populations

A community is all the populations of all species living in an ecosystem

An arctic community might include populations of fish, seals that eat fish, and polar bears that hunt and eat seals

Populations

This figure shows how organisms, populations, communities, and ecosystems are related