Write the general characters of phylum Annelida.

Explanation

The general characters of phylum annelida are as follows:
(i) The body is divided into segments or metameres by ring-like grooves, the annuli.
(ii) The symmetry is bilateral in annelids. The annelids are triploblastic.
(iii) There is organ-system level of organisation.
(iv) The anterior end bears a distinct head.
(v). Annelids have simple unjointed locomotory organs, the parapodia, on the sides of the body
(vi) The body wall is covered by a thin, moist cuticle, single layered epidermis and well developed musculature Body wall may have minute chitinous setae in it.
(vii) A true coelom present in the body cavity. It is schizocoel.
(viii) There is hydrostatic skeleton.
(ix) Respiration occurs through skin. It is called cutaneous respiration.
(x) Circulatory system is closed. Haemoglobin is dissolved in plasma so this blood is red.
(xi) The excretory system consists of coiled tubules, the nephridia. It is also responsible for osmoregulation
(xii) Asexual reproduction occurs by budding or fission. Animals may be unisexual or hermaphrodite