1. In the gaseous stage of the process, carbon moves about as mostly carbon dioxide
2. In the sedimentary stage of the process, carbon is found
in organic materials.
3. The world's supply of carbon dioxide is held in an atmospheric pool.
4. Carbon dioxide leaves the pool and enters the ocean where phytoplankton use
it in photosynthesis.
5. Phytoplankton make calcium carbonate and it settles to the ocean floor to build
up as sedimentary strata.
6. Other organic materials are made by phytoplankton and sink to the ocean floor
where they eventually become hydrocarbons used in making petroleum and natural gas.
7. On land, plants build up layers of peat that are eventually transformed into