Here are entered works on energy from fuels produced from plant or animal sources, such as forestry byproducts or agricultural waste, or on the fuels themselves. Works on the total mass of living matter within a given unit of environmental area are entered under Biomass.
--subdivisions Metabolism--Regulation, Secretion--Regulation, and Synthesis--Regulation under individual chemicals and groups of chemicals, e.g. Copper--Metabolism--Regulation; Copper--Secretion--Regulation; Insulin--Synthesis--Regulation; and subdivision Vocalization--Regulation under individual animals and groups of animals, e.g. Mammals--Vocalization--Regulation; Cattle--Vocalization--Regulation