In chemistry, glycosies are certain molecules in which a sugar part is bound to some other part. Glycosides play numerous important roles in living organisms. Many plants store important chemicals in the form of inactive glycosides; if these chemicals are needed, the glycosides are brought in contact with water and an enzyme, and the sugar part is broken off, making the chemical available for use. Many such plant glycosides are used as medications. In animals (including humans), poisons are often bound to sugar molecules in order to remove them from the body.