Carbon is found in the non-living part of the hydrosphere, atmosphere, and Geo-sphere, as carbonate (CaCO3) rocks and dead organic matter, such as humus in soil.
Biotic means that it emanates from life. Carbohydrates are made through photosynthesis of plants and other autotrophs. The carbon dioxide is absorbed from the atmosphere by the living organism and used to make carbohydrates like glucose by reducing the carbon dioxide.
