Answer the following questions in detail

Question

Enlist the characteristic features of phylum Annelida.

Vidyadip · Accepted Answer

Annelids are commonly called as ring worms or segmented worms.
Characteristic feature of phylum Annelida:

Forms: Annelids may be aquatic, ectoparasitic or free – living or burrowing in moist soil.
Body symmetry: They are bilaterally symmetrical.
Body coelom: They are true coelomates.
Segmentation: Body is metamerically segmented and has a special region called clitellum.
Digestive system: Alimentary canal is complete.
Locomotion: Locomotion takes place with the help of setae (earthworm), parapodia (Nereis) or suckers (leech). Well developed longitudinal and circular muscles help in locomotion.
Nervous system: It consists of nerve ring and ventral solid and ganglionated nerve cord.
Reproduction: Mostly are hermaphrodites and few are dioecious (Nereis).
Respiration: Exchange of gases takes place through body wall.
Circulation: Circulatory system is of closed type. Excretion and osmoregulation is carried out with help of nephridia. e.g. Nereis (Aquatic annelid), Pheretima (Earthworm), Hirudinaria (Leech).

Answer