Energy flows from the environment into living organisms, then back to the environment

The flow drives a cycling of materials among producers and consumers.

A Energy In. Sunlight energy reaches environments on Earth. Producers in those environments capture some of the energy and convert it to other forms that can drive cellular work.

B Some of the energy captured by producers ends up in the tissues of consumers.

C Energy Out. With each energy transfer, some energy escapes into the environment, mainly as heat. Living things do not use heat to drive cellular work, so energy flows through the world of life in one direction overall.