Theme 6:

Human Influence on the Environment

In previous themes in this course, you learned about properties of matter and energy transfer technologies. You also investigated matter and energy in living systems. Now you will investigate matter and energy in environmental systems.

In this theme, you will learn that energy from the sun sustains living systems and that matter is recycled along natural pathways, called food chains, food webs, and energy pyramids. You will also learn the impact that increasing human population and activities has had on these pathways.