Sore throat is a symptom, not a disease. In each case, there was a different cause that dictated a different treatment. The scratchy throat probably was a mechanical problem caused by dry, heated winter air and aggravated by my friend's tendency to breathe through her mouth when she sleeps.
Biogeochemistry includes the history of the great carbon reservoirs in the crust of the Earth, like limestone rocks and the coal deposits, as well as the distribution of nitrate and phosphate in the ocean.
Carbon that is a part of rocks and fossil fuels like oil, coal, and natural gas may be held away from the rest of the carbon cycle for a long time. These long-term storage places are called âsinksâ. When fossil fuels are burned, carbon that had been underground is sent into the air as carbon dioxide, a greenhouse gas.