Most autotrophs use water as the reducing agent, but some can use other hydrogen compounds such as hydrogen sulfide. Phototrophs (green plants and algae), a type of autotroph, convert electromagnetic energy from sunlight into chemical energy in the form of reduced carbon.
Athens is a city in and the county seat of Athens County, Ohio, United States. It is located along the Hocking River in the southeastern part of Ohio. A historic college town, Athens is home to Ohio University (26,000+ students) and is the principal city of the Athens, Ohio Micropolitan Statistical Area. The official population of Athens in the 2010 U.S. Census was 23,832.
Limestone County is a county of the U.S. state of Alabama. As of the 2010 census, the county's population was 82,782. Its county seat is Athens. Its name comes from Limestone Creek, a local stream.