give the characteristics of the following:

Features:

i) Aquatic, mostly marine.

ii) multicellular, diploblastic animals.

iii) A central gastrovascular cavity called coelenteron is present.

iv) Some live in colonies, while others are solitary.

v) Possess specialised cells called cnidoblasts which bear stinging cells.

vi) Nervous system primitive.

vii) Both sexual and asexual reproduction seen.