Broader definitions of chemicals or chemical substances can be found, for example: the term 'chemical substance' means any organic or inorganic substance of a particular molecular identity, including â (i) any combination of such substances occurring in whole or in part as a result of a chemical reaction or occurring in nature.
The major groups of worms include various species of flatworm, annelid, ribbon worm, spiny-headed worm, and aschelminth. Worms typically have an elongated, tubelike body, usually rather cylindrical, flattened, or leaflike in shape and often without appendages.
Worms are soft, long-bodied invertebrates, or animals without a backbone. There are at least 20,000 species, or kinds, of worm. They are not all related. In fact, they belong to several different animal groups.orms are soft, long-bodied invertebrates, or animals without a backbone. There are at least 20,000 species, or kinds, of worm. They are not all related. In fact, they belong to several different animal groups.