Think about it 1. Living organisms are composed mostly of four elements: , , , and .
Recycling in the Biosphere
2. Unlike the -way flow of energy, matter is within and between .
3. What are biogeochemical cycles?
4. What three processes are involved in the cycling of matter?
A.
B.
C.

1. Carbon, hydrogen, oxygen, and nitrogen, 2. high, measured speed.    3. Biogeochemical cycle, any of the natural pathways by which essential elements of living matter are circulated. The term biogeochemical is a contraction that refers to the consideration of the biological, geological, and chemical aspects of each cycle. 4. These three processes move water into the atmosphere. Evaporation occurs when water on Earth's surface changes to water vapor.

Explanation:

a "theory" a suggestion that is not 100 % accurate, or a figure. some people say its a theory because they of all the passed theory's about one subject. it depends sometimes theory might be accurate and sometimes they are.