<unk>  is the metabolism of<unk> s, their biochemical modification or degradation, usually through specialized enzymatic systems.<unk>  often converts lipophilic chemical compounds into more readily excreted polar products. Its rate is an important determinant of the duration and intensity of the pharmacological action of<unk> s.<unk>  can result in toxication or detoxication - the activation or deactivation of the chemical.
While both occur, the major metabolites of most<unk> s are detoxication products.<unk> s are almost all xenobiotics.
Other commonly used organic chemicals are also<unk> s, and are metabolized by the same enzymes as<unk> s.
This provides the opportunity for<unk> -drug and<unk> -chemical interactions or reactions.
Drug metabolism
Cell signaling
Photosynthesis
Carbohydrate metabolism
Heat transfer
Coagulation
Signal transduction
Wound healing