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.
The pinworm, also known as the threadworm or seatworm, but most formally known as the Enterobius vermicularis, is a very common intestinal parasite that infect humans, mostly children. Enterobiasis refers to the disease associated with the pinworm infestation in the body.