MeSH definition : A heterogeneous class of water-soluble compounds containing covalently bound CARBON
that are derived from a variety of biological and geological sources during the biogeochemical
cycling of carbon (CARBON CYCLE).;
A heterogeneous class of water-soluble compounds containing covalently bound CARBON
that are derived from a variety of biological and geological sources during the biogeochemical
cycling of carbon (CARBON CYCLE).