Answer:
Helminths are metazoans, multicellular animals, not vertebrates, without articulated appendages and with a musculoskeletal envelope that surrounds the general cavity or celoma.
Explanation:
Under the cuticle they have the muscular layer, responsible for the movement. The digestive system is a long tube with two openings, a mouth and an anus. They lack circulatory system and respiratory organs. The nervous system is formed by a pair of ganglia from which the nerve branches that are arranged longitudinally. They have developed sexual organs. The cestodes and most of the trematodes are hermaphrodites.
The helminths of interest in human pathology are divided into two Phylum:
-Nematoda: cylindrical worms, not segmented and with separate sexes.
-Platyhelminthes: flat worms, can be segmented and also hermaphroditic.