Write the general characters of the phylum cnidaria.

Explanation

1.The cnidaria are aquatic, radially symmetrical and diploblastic.
2. The tentacles have stinging cells called cnidocytes.or cnidoblasts or nematocysts.
3. They exhibit tissue level of organisation.
4. They have a central gastrovascular cavity called coelenderon.
5. Digestion is by both extracellular and intracellular.
6. Alternation of generation is seen in cnidarians which have polyp and medusa forms.
7. Development is indirect with planula larva e.g. Physalia.