Answer:
Most autotrophs—organisms able to produce their own energy—are photosynthetic: They require sunlight and oxygen. The extremophiles of Blood Falls, however, do not use photosynthesis. They use a more unusual process called chemosynthesis. Chemosynthetic organisms are able to convert sulfur and iron compounds (not sunlight and oxygen) into energy. As Blood Falls’ chemosynthetic bacteria extract iron from the rocks they come in contact with, they gradually erode the bedrock around the lake.
Explanation:
